Infusion medium delivery device and method with drive device for driving plunger in reservoir

ABSTRACT

A delivery device includes a durable housing portion and a separable disposable portion that selectively engage and disengage from each other. The disposable housing portion secures to the patient-user and may be disposed of after it has been in use for a prescribed period. Components that normally come into contact with a patient-user or with infusion medium are supported by the disposable housing portion, while the durable housing portion supports other components such as electronics and a drive device. A reservoir is supported by the disposable housing portion and has a moveable plunger that operatively couples to the drive device, when the disposable and durable housing portions are engaged.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

The present application is a Continuation-In-Part of U.S. patentapplication Ser. No. 11/588,832, filed on Oct. 27, 2006, (attorneydocket no. 047711.0387), which is incorporated herein by reference inits entirety. This application claims priority from ProvisionalApplication U.S. Application 60/839,822, filed Aug. 23, 2006,incorporated herein by reference in its entirety. The present inventionalso relates to U.S. Provisional Patent Application 60/678,290, filedMay 6, 2005 and U.S. patent application Ser. No. 11/211,095, filed Aug.23, 2005, each of which is incorporated herein by reference in itsentirety. The present invention also relates to co-pending applicationNo. 60/839,821, titled SYSTEMS AND METHODS ALLOWING FOR RESERVOIRFILLING AND INFUSION MEDIUM DELIVERY, filed Aug. 23, 2006, (attorneydocket no. 047711-0381); co-pending application No. 60/839,832, titledINFUSION MEDIUM DELIVERY DEVICE AND METHOD WITH COMPRESSIBLE OR CURVEDRESERVOIR OR CONDUIT, filed Aug. 23, 2006, (attorney docket no.047711-0383); co-pending application No. 60/839,840, titled INFUSIONMEDIUM DELIVERY SYSTEM, DEVICE AND METHOD WITH NEEDLE INSERTER ANDNEEDLE INSERT DEVICE AND METHOD, filed Aug. 23, 2006, (attorney docketno. 047711-0384); and co-pending application No. 60/839,741, titledINFUSION PUMPS AND METHODS AND DELIVERY DEVICES AND METHODS WITH SAME,filed Aug. 23, 2006, (attorney docket no. 047711-0385). Embodiments ofthe present invention also relate to: (i) U.S. patent application Ser.No. 11/588,875, filed Oct. 27, 2006, entitled “Systems And MethodsAllowing For Reservoir Filling And Infusion Medium Delivery” (attorneydocket no. 047711.0393); (ii) U.S. patent application Ser. No.11/588,847, filed Oct. 27, 2006, entitled “Infusion Medium DeliveryDevice and Method with Compressible or Curved Reservoir or Conduit”(attorney docket no. 047711.0390); (iii) U.S. Provisional PatentApplication Ser. No. 60/854,829, filed Oct. 27, 2006, entitled “InfusionMedium Delivery System, Device and Method with Needle Inserter andNeedle Inserter Device and Method” (attorney docket no. 047711.0401);and (iv) U.S. patent application Ser. No. 11/589,323, filed Aug. 23,2006, entitled “Infusion Pumps and Methods and Delivery Devices andMethods with Same” (attorney docket no. 047711.0398), the contents ofeach of which are incorporated by reference herein, in their entirety.

FIELD OF THE INVENTION

Embodiments of the present invention relate to an infusion mediumdelivery device for delivering an infusion medium to a patient-user,where the delivery device includes a base portion and a durable portionconnectable to the base portion, where the base portion is securable toa patient-user's skin and can be removed and disposed of after aspecified number of uses.

BACKGROUND OF THE INVENTION

Certain chronic diseases may be treated, according to modern medicaltechniques, by delivering a medication or other substance to a patient'sbody, either in a continuous manner or at particular times or timeintervals within an overall time period. For example, diabetes is achronic disease that is commonly treated by delivering defined amountsof insulin to the patient at appropriate times. Some common modes ofproviding an insulin therapy to a patient include delivery of insulinthrough manually operated syringes and insulin pens. However, othermodern systems employ programmable pumps to deliver controlled amountsof insulin to a patient.

Pump type delivery devices have been configured in external devices(that connect to a patient) or implantable devices (to be implantedinside of a patient's body). External pump type delivery devices includedevices designed for use in a stationary location (for example, in ahospital or clinic), and further devices configured for ambulatory orportable use (to be carried by a patient). Examples of some externalpump type delivery devices are described in Published PCT Application WO01/70307 (PCT/US01/09139) titled “Exchangeable Electronic Cards ForInfusion Devices” (which is owned by the assignee of the presentinvention), Published PCT Application WO 04/030716 (PCT/US2003/028769)titled “Components And Methods For Patient Infusion Device,” PublishedPCT Application WO 04/030717 (PCT/US2003/029019) titled “DispenserComponents And Methods For Infusion Device,” U.S. Patent ApplicationPublication No. 2005/0065760 titled “Method For Advising PatientsConcerning Doses Of Insulin,” and U.S. Pat. No. 6,589,229 titled“Wearable Self-Contained Drug Infusion Device,” each of which isincorporated herein by reference in its entirety.

External pump type delivery devices may be connected in fluid-flowcommunication to a patient-user, for example, through a suitable hollowtubing. The hollow tubing may be connected to a hollow needle designedto pierce the patient-user's skin and deliver an infusion mediumthere-through. Alternatively, the hollow tubing may be connecteddirectly to the patient-user as or through a cannula or set ofmicro-needles.

In contexts in which the hollow tubing is connected to the patient-userthrough a hollow needle that pierces the patient-user's skin, a manualinsertion of the needle into the patient-user can be somewhat traumaticto the patient-user. Accordingly, insertion tools have been made toassist the insertion of a needle into the patient-user, whereby a needleis forced by a spring to quickly move from a retracted position into anextended position. One example of such an insertion tool is described inU.S. Patent Application Publication No. 2002/0022855, titled “InsertionDevice For An Insertion Set And Method Of Using The Same” (assigned tothe assignee of the present invention), which is incorporated herein byreference in its entirety. As the needle is moved into the extendedposition, the needle is quickly forced through the patient-user's skinin a single, relatively abrupt motion that can be less traumatic to apatient-user as compared to a slower, manual insertion of a needle.However, in some contexts, a controlled, slow insertion speed can beless traumatic to some patients.

As compared to syringes and insulin pens, pump type delivery devices canbe significantly more convenient to a patient-user, in that accuratedoses of insulin may be calculated and delivered automatically to apatient-user at any time during the day or night. Furthermore, when usedin conjunction with glucose sensors or monitors, insulin pumps may beautomatically controlled to provide appropriate doses of infusion mediumat appropriate times of need, based on sensed or monitored levels ofblood glucose.

Pump type delivery devices have become an important aspect of modernmedical treatments of various types of medical conditions, such asdiabetes. As pump technologies improve and doctors and patient-usersbecome more familiar with such devices, the popularity of externalmedical infusion pump treatment increases and is expected to increasesubstantially over the next decade.

SUMMARY OF THE DISCLOSURE

Embodiments of the present invention relate to an infusion mediumdelivery device for delivering an infusion medium to a patient-user,wherein the delivery device includes a first (or durable) housingportion and a second (or disposable) housing portion that selectively,engage and disengage from each other, for example, by manual force. Oneor both of the first and second housing portions secures to thepatient-user. The disposable housing portion may be disposed of after ithas been in use for a prescribed period. Components that normally comeinto contact with a patient-user and/or with infusion media may besupported by the disposable housing portion for disposal after theprescribed use, while the durable housing portion supports othercomponents such as electronics for controlling the delivery of infusionmedia.

According to embodiments of the invention, a delivery device includesfirst and second housing portions as described above and a reservoirlocated in the first housing portion. The reservoir has an interior forcontaining a fluidic medium and a plunger is moveable within theinterior of the reservoir along an axial direction of the reservoir. Arotatable shaft is disposed at least partially within the reservoirinterior, along the axial direction of the reservoir.

In an example embodiment, the rotatable shaft extends through a threadedchannel in the plunger and has a threaded portion that is operativelyengaged with the threaded channel of the plunger. Rotation of therotatable shaft causes the plunger to move along the length of thethreaded portion of the rotatable shaft to vary the interior volume ofthe reservoir. A drive device is supported by the durable housingportion in a position to operatively connect to the rotatable shaft, toselectively rotate the rotatable shaft, when the disposable and durablehousing portions are engaged.

A delivery device according to the above-described embodiment may alsoinclude at least one seal arranged between the rotatable shaft and theplunger, to inhibit the passage of the fluidic medium through thecentral channel of the plunger. The seal may comprise at least one layerof sealing material disposed over the rotatable shaft. In anotherembodiment, the seal comprises a plurality of o-ring seals disposedaround the rotatable shaft.

A delivery device for delivering an infusion medium to a patient-useraccording to a further example embodiment also includes first and secondhousing portions and a reservoir as described above. In this furtherexample, embodiment, a plunger moveable within the reservoir and a slidemember having an end for engaging the plunger is supported by thedurable housing portion. The slide member has a threaded, at leastpartially generally cylindrical surface. A rotatable shaft is supportedby the durable housing portion and extends along the threaded surface ofthe slide member and has a threaded portion operatively engaged with thethreaded surface of the slide member to move the slide member in theaxial direction of the reservoir by rotation of the rotatable shaftrelative to the slide member. A drive device is supported by the durablehousing portion and is operatively coupled to the rotatable shaft toselectively rotate the rotatable shaft. In such an embodiment, movementof the slide member by the rotation of the rotatable shaft istransferred to movement of the plunger in the axial direction of thereservoir, when the slide member is engaged with the plunger.

A delivery device according to the above-described further exampleembodiment may also include an anti-rotation structure for inhibitingrotation of the slide member around the axial direction. Also, the slidemember may extend through an aperture in the durable housing portion andat least one seal member may be provided around the aperture. The slidemember may include a tube structure that has a hollow, generallycylindrical interior, wherein the threaded surface of the slide memberis at least a portion of an interior surface of the tube structure.Alternatively, the slide member may include a partial tube structurehaving a hollow, semi-cylindrical interior, wherein the threaded surfaceof the slide member is at least a portion of a semi-cylindrical interiorsurface of the partial tube structure.

A delivery device according to the above-described further exampleembodiment may include a second reservoir supported by the disposablehousing portion and having an interior for containing a fluidic medium,and a second plunger moveable within the interior of the secondreservoir along an axial direction of the second reservoir. In such anembodiment, a second slide member is supported by the durable housingportion and has an end for engaging the second plunger when thedisposable housing portion and durable housing portion are engaged. Thesecond slide member also has a threaded, at least partially generallycylindrical surface. A second rotatable shaft is supported by thedurable housing portion and extends along the threaded surface of thesecond slide member. The second rotatable shaft has a threaded portionoperatively engaged with the threaded surface of the second slide memberto move the second slide member in the axial direction of the secondreservoir by rotation of the second rotatable shaft relative to thesecond slide member. In such an embodiment, the drive device is alsooperatively coupled to the second rotatable shaft to selectively rotatethe second rotatable shaft. Movement of the second slide member by therotation of the second rotatable shaft is transferred to movement of thesecond plunger in the axial direction of the second reservoir, when thesecond slide member is engaged with the second plunger.

A delivery device for delivering an infusion medium to a patient-useraccording to a further example embodiment also includes first and secondhousing portions, a reservoir and a plunger moveable within thereservoir as described above. In addition, this further embodimentincludes a slide member supported by the durable housing portion, wherethe slide member has an end for engaging the plunger when the disposablehousing portion and durable housing portion are engaged, and the slidemember also has an engagement surface for engaging a drive surface of apiezoelectric stack drive device. In this further embodiment, a shaft issupported by the durable housing portion and extends along theengagement surface of the slide member. A piezoelectric stack drivedevice is supported by the shaft and is arranged to operatively engagethe slide member to selectively move the slide member in the axialdirection of the reservoir. Movement of the slide member by operation ofthe piezoelectric stack drive device is transferred to movement of theplunger in the axial direction of the reservoir, when the slide memberis engaged with the plunger.

A delivery device according to the above-described further exampleembodiment also may also include at least one seal arranged between therotatable shaft and the plunger, to inhibit the passage of the fluidicmedium through the central channel of the plunger. The seal may compriseat least one layer of sealing material disposed over the rotatableshaft. In another embodiment, the seal comprises a plurality of o-ringseals disposed around the rotatable shaft. Also, in the above-describedfurther example embodiment, the slide member may include a tubestructure that has a hollow, generally cylindrical interior and theengagement surface of the slide member may include at least a portion ofan interior surface of the tube structure.

A delivery device for delivering an infusion medium to a patient-useraccording to yet a further example embodiment also includes first andsecond housing portions, a reservoir and a plunger moveable within thereservoir as described above. In addition, this further embodimentincludes an expandable structure that has an interior volume and an endfor engaging the plunger and moving the plunger as the expandablestructure is expanded, when the disposable housing portion and thedurable housing portion are engaged. The expandable structure mayinclude a bellows structure. This further embodiment also includes asecond reservoir supported by the durable housing portion, forcontaining a second fluid medium for expanding the expandable structureand a conduit for coupling the second reservoir to an interior volume ofthe expandable structure. In addition, a drive device is supported bythe durable housing portion, for selectively conveying the secondfluidic medium through the conduit, from the second reservoir to theinterior volume of the expandable structure, to selectively expand theexpandable structure, when the first housing portion and the secondhousing portion are engaged.

In the above-described further example embodiment, the drive device mayinclude a peristaltic drive device or other type of fluid pump. In suchan embodiment, the peristaltic drive device may include a rotatablerotor that has a plurality of contact rollers or pads arranged tocontact a first length of the conduit as the rotor is rotated, and asupport surface may be provided on the durable housing portion forsupporting at least the first length of the conduit. The support surfacemay include a curved surface. The drive device may include a motoroperatively coupled to rotate the rotatable rotor. A linkage structuremay be coupled to the motor and to the rotatable rotor, to transferdrive force from the motor to the rotatable rotor.

Alternatively, in the above-described further example embodiment, thedrive device may include a rotatable rotor having a plurality of contactrollers or pads arranged to contact a first length of the conduit as therotor is rotated along a radius of curvature. In such embodiment, acurved surface is provided on the durable housing portion for supportingat least the first length of the conduit, where the curved surfacehaving a radius of curvature approximating the radius of curvature ofthe rotor rollers or pads. A motor may be operatively coupled to rotatethe rotatable rotor.

In any of the above-described embodiments, the durable housing portionmay have an enclosed interior volume that contains the drive device, andthe drive device may be operatively connected to a connection end of therotatable shaft through a drive linkage that extends through an aperturein the durable housing portion. In such an embodiment, a connection endof the drive linkage and the connection end of the rotatable shaft havemating shapes that mate together and allow transfer of rotational motionfrom the drive linkage to the rotatable shaft, when the disposable anddurable housing portions are engaged. Also, in such an embodiment, aseal may be provided adjacent the aperture in the durable housingportion, to seal the aperture through which the drive linkage extends.

A delivery device according to any of the above-described embodimentsmay include electrical control circuitry contained in the durablehousing portion. The electrical control circuitry controls the deliveryof infusion medium from the reservoir to the patient-user when thedurable housing portion and the disposable housing portion are engaged.

In any of the above-described embodiments, the disposable housingportion may include a base portion having a bottom surface and anadhesive material on the bottom surface for securing the disposablehousing portion to the skin of the patient-user. Also, in any of theabove-described embodiments, the reservoir may include a septum that maybe pierced by a hollow needle for providing a fluid flow path from theinterior of the reservoir to the hollow needle.

Also, any of the above-described embodiments may further include ananti-rotation structure to inhibit the plunger from rotating within thereservoir. In such embodiments, the anti-rotation structure may includeat least one projection extending from one of the plunger and theinterior surface of the reservoir and at least one channel provided inthe other one of the plunger and the interior surface of the reservoir.Each projection is configured to extend at least partially into achannel.

Also, in any of the above-described embodiments, at least one seal maybe arranged around the outer peripheral surface of the plunger, forinhibiting the passage of infusion medium between the outer peripheralsurface of the plunger and an interior surface of the reservoir.

In any of the above-described embodiments, a linkage structure may beprovided for operatively coupling the drive device to the rotatableshaft. Also, in any of the above-described embodiments, the drive devicemay include a rotary motor operatively connected to rotate the rotatableshaft. Alternatively, or in addition, the drive device may include anescapement wheel that is supported for rotation and is operativelyconnected to rotate the rotatable shaft and/or drive linkage withrotation of the escapement wheel. In such embodiments, an actuator isoperatively connected to the escapement wheel for selectively rotatingthe escapement wheel. For example, a drive pawl may be supported forlinear movement between a start position and an end position and mayhave a drive surface arranged to engage a tooth of the escapement wheeland rotate the escapement wheel in a first direction as the drive pawlmoves between the start and end positions. An actuator may beoperatively connected to the drive pawl, for selectively moving thedrive pawl from the start position to the end position.

Further embodiments of the present invention relate to methods of makinga delivery device for delivering an infusion medium to a patient-user.Such methods include providing a first housing portion adapted to besecured to a patient-user and providing a second housing portionconfigured to be selectively engaged with and disengaged from the firsthousing portion to allow disposal of the first housing portion withoutdisposing of the second housing portion. Such methods further includesupporting a reservoir on the first housing portion, the reservoirhaving an interior for containing a fluidic medium and arranging aplunger within the interior of the reservoir and moveable relative tothe reservoir along an axial direction of the reservoir. Such methodsfurther include arranging a rotatable shaft at least partially withinthe reservoir interior, along the axial direction of the reservoir,extending the rotatable shaft through the threaded channel of theplunger, and operatively engaging a threaded portion of the rotatableshaft with the threaded channel of the plunger. In such embodiments,rotation of the rotatable shaft relative to the plunger causes theplunger to move along the length of the threaded portion of therotatable shaft to vary the interior volume of the reservoir. Suchembodiments further include supporting a drive device on the secondhousing portion in a position to operatively connect to the rotatableshaft, to selectively rotate the rotatable shaft, when the first andsecond housing portions are engaged.

Further method embodiments include arranging at least one seal betweenthe rotatable shaft and the plunger, to inhibit the passage of thefluidic medium through the central channel of the plunger. In oneexample, arranging at least one seal includes providing at least onelayer of sealing material over the rotatable shaft. In another example,arranging at least one seal includes providing a plurality of o-ringseals disposed around the rotatable shaft.

A method for making a delivery device for delivering an infusion mediumto a patient-user according to a further example embodiment alsoincludes providing first and second housing portions and supporting areservoir as described above. In this further example, embodiment, amethod includes arranging a plunger within the interior of the reservoirand movable along an axial direction of the reservoir. A methodaccording to this further example also includes supporting a slidemember on the second housing portion, with an end of the slide memberarranged to engage the plunger when the first housing portion and thesecond housing portion are engaged. In addition this method includessupporting a rotatable shaft on the second housing portion, extendingthe rotatable shaft along the threaded surface of the slide member andoperatively engaging a threaded portion of the rotatable shaft with thethreaded surface of the slide member to move the slide member in theaxial direction of the reservoir by rotation of the rotatable shaftrelative to the slide member. This method also includes operativelycoupling a drive device to the rotatable shaft to selectively rotate therotatable shaft, such that movement of the slide member by the rotationof the rotatable shaft is transferred to movement of the plunger in theaxial direction of the reservoir, when the slide member is engaged withthe plunger.

A method according to the above further example embodiment may furtherinclude providing an anti-rotation structure for inhibiting rotation ofthe slide member relative to the reservoir. A method according to theabove further example embodiment also may include extending the slidemember through an aperture in the second housing portion and providingat least one seal member around the aperture. In a method according tothe above further example embodiment, supporting a slide member mayinclude supporting a tube structure on the second housing portion, wherethe tube structure has a hollow, generally cylindrical interior and thethreaded surface of the slide member includes at least a portion of agenerally cylindrical interior surface of the tube structure.Alternatively, supporting a slide member may include supporting apartial tube structure on the second housing portion, where the partialtube structure has a hollow, semi-cylindrical interior and the threadedsurface of the slide member includes at least a portion of asemi-cylindrical interior surface of the partial tube structure.

A method according to the above-described further example embodiment mayfurther include supporting a second reservoir on the first housingportion, where the second reservoir has an interior for containing afluidic medium. This further method also includes arranging a secondplunger within the interior of the second reservoir and moveable alongan axial direction of the second reservoir and supporting a second slidemember on the second housing portion in a position at which an end ofthe second slide member engages the second plunger when the firsthousing portion and the second housing portion are engaged, the secondslide member further having a threaded, at least partially generallycylindrical surface. This further method also includes supporting asecond rotatable shaft on the second housing portion and extending athreaded portion of the second rotatable shaft along the threadedsurface of the second slide member to operatively engage with thethreaded surface of the second slide member and to move the second slidemember in the axial direction of the second reservoir by rotation of thesecond rotatable shaft relative to the second slide member when thefirst housing portion and the second housing portion are engaged. Inthis further method embodiment, the drive device is also operativelycoupled to the second rotatable shaft to selectively rotate the secondrotatable shaft and movement of the second slide member by the rotationof the second rotatable shaft is transferred to movement of the secondplunger in the axial direction of the second reservoir, when the secondslide member is engaged with the second plunger.

A method for making a delivery device for delivering an infusion mediumto a patient-user according to a further example embodiment alsoincludes providing first and second housing portions, supporting areservoir and arranging a plunger within the interior of the reservoirand movable along an axial direction of the reservoir, as describedabove. A method according to this further example also includessupporting arranging an end of an expandable structure for engaging theplunger and moving the plunger as the expandable structure is expanded,when the first housing portion and the second housing portion areengaged. Such a method embodiment further includes supporting a secondreservoir on the second housing portion, for containing a second fluidmedium for expanding the expandable structure. In addition, such amethod embodiment includes coupling a conduit in fluid flowcommunication with the second reservoir and an interior volume of theexpandable structure and operatively coupling a drive device forselectively conveying the second fluidic medium through the conduit,from the second reservoir to the interior volume of the expandablestructure, to selectively expand the expandable structure, when thefirst housing portion and the second housing portion are engaged.

In a method according to the above-described further example embodiment,operatively coupling a drive device may include operatively coupling aperistaltic drive device to the conduit. Alternatively or in addition,operatively coupling a drive device may include supporting a rotatablerotor for rotation and arranging the rotatable rotor having a pluralityof contact rollers or pads to contact a first length of the conduit asthe rotor is rotated when the first and second housing portions areengaged. Such an embodiment may further include providing a supportsurface for supporting the first length of conduit. The support surfacemay be curved. Supporting a first length of the conduit may includearranging a curved surface to support the first length of the conduit,where the curved surface has a radius of curvature approximating theradius of curvature of the rotor rollers or pads. Such an embodimentalso may include peratively coupling a motor to rotate the rotatablerotor. Operatively coupling a motor may include coupling a linkagestructure to the motor and to the rotatable rotor, to transfer driveforce from the motor to the rotatable rotor.

In any of the above-described method embodiments, the method may furtherinclude extending a drive linkage through an aperture in the secondhousing portion to a position to operatively connect to a connection endof the rotatable shaft when the first and second housing portions areengaged, and coupling drive linkage with the drive device, fortransmitting drive force from the drive device to the rotatable driveshaft when the first and second housing portions are engaged. A seal maybe arranged adjacent the aperture in the durable housing portion, toseal the aperture through which the drive linkage extends. Such methodembodiments may further include providing the drive linkage with aconnection end for connecting to the connection end of the rotatableshaft, and providing the connection end of the drive linkage and theconnection end of the rotatable shaft with mating shapes that matetogether and allow transfer of rotational motion from the drive linkageto the rotatable shaft, when the first and second housing portions areengaged.

Any of the above-described method embodiments may further includesupporting electrical control circuitry on the second housing portion,where the electrical control circuitry controls the delivery of infusionmedium from the reservoir to the patient-user when the first housingportion and the second housing portion are engaged. Also, in any of theabove-described method embodiments, providing a first housing portionmay include providing a base portion having a bottom surface and anadhesive material on the bottom surface for securing the base to theskin of the patient-user. Also, any of the above-described methodembodiments may further include supporting a septum that may be piercedby a hollow needle for providing a fluid flow path from the interior ofthe reservoir to the hollow needle.

Also, any of the above-described method embodiments may further includeproviding an anti-rotation structure to inhibit the plunger fromrotating within the reservoir. In such embodiments, providing ananti-rotation structure may include providing at least one projectionextending from one of the plunger and the interior surface of thereservoir and providing at least one channel in the other one of theplunger and the interior surface of the reservoir, where the at leastone projection is configured to extend at least partially into the atleast one channel.

Any of the above-described method embodiments may further includearranging at least one seal around an outer peripheral surface of theplunger, for inhibiting the passage of infusion medium between the outerperipheral surface of the plunger and an interior surface of thereservoir.

In any of the above-described method embodiments, operatively coupling adrive device may include coupling a linkage structure to the drivedevice and to the rotatable shaft. Also in any of the above-describedembodiments, operatively coupling a drive device may include operativelycoupling a rotary motor to rotate the rotatable shaft. Alternatively, orin addition, operatively coupling a drive device may include supportingan escapement wheel for rotation, operatively connecting the escapementwheel to the rotatable shaft to rotate the rotatable shaft with rotationof the escapement wheel and operatively connecting an actuator to theescapement wheel for selectively rotating the escapement wheel.

In any of the above-described method embodiments, supporting a drivedevice may include supporting an escapement wheel for rotation, wherethe escapement wheel is operatively connected to rotate the drivelinkage with rotation of the escapement wheel. Such method embodimentsfurther include supporting a drive pawl for linear movement between astart position and an end position, where the drive pawl has a drivesurface arranged to engage a tooth of the escapement wheel and rotatethe escapement wheel in a first direction as the drive pawl movesbetween the start and end positions. Such method embodiments furtherinclude operatively connecting an actuator to the drive pawl, forselectively moving the drive pawl from the start position to the endposition.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a generalized diagram of a delivery system in relation to ahuman patient-user.

FIG. 2 is a perspective view of a delivery device according to anembodiment of the invention.

FIG. 3 is a perspective view of a durable portion and a disposableportion of the delivery device of FIG. 2, with the durable portionseparated from the disposable portion.

FIG. 4 is a schematic, cross-sectional view of the interior of areservoir and a durable housing portion of a delivery device accordingto an embodiment of the invention.

FIG. 5 is a schematic, cross-sectional view of a portion of a reservoir,showing an arrangement of a hollow needle or cannula piercing thereservoir septum and a patient-user's skin.

FIG. 6 is a perspective view of a durable portion separated from adisposable portion of a delivery device having a reservoir, pistonplunger and lead shaft configuration that engage in a manner similar tothat of FIG. 4.

FIG. 7 is a schematic, cross-section view of the piston plunger and leadshaft of FIG. 6, in an engaged state.

FIG. 8 is a schematic, side view of a motor and linkage structure thatmay be employed with the embodiments of FIGS. 4, 6 and 7.

FIG. 9 is a side view of the motor and linkage structure of FIG. 8, asviewed from the left side of FIG. 8.

FIG. 10 is a side view of the motor and linkage structure of FIG. 8, asviewed from the right side of FIG. 8.

FIG. 11 a is a schematic, cross-sectional view of a portion of areservoir and a portion of a lead shaft according to another embodimentof the invention.

FIG. 11 b is a further view of the piston shaft of FIG. 11, along thelongitudinal axis of the piston shaft.

FIG. 12 is a perspective view of an embodiment of a reservoir, pistonplunger and lead shaft suitable for the delivery device embodiments ofFIGS. 4, 6 and 7.

FIG. 13 is an axial view of the piston plunger of FIG. 12, with the clipopen.

FIG. 14 is an axial view of the piston plunger of FIG. 12, with the clipclosed.

FIG. 15 is a perspective view of the piston plunger of FIG. 12 assembledwith the reservoir of FIG. 12, and with the lead shaft of FIG. 12 inoperable engagement with the piston plunger.

FIGS. 16 a-d show schematic views of escapement wheel arrangements andcomponents thereof, for providing a controlled rotational motion.

FIG. 17 shows a schematic view of a delivery device according to afurther embodiment of the present invention.

FIG. 18 shows a schematic, cross-sectional view of a reservoir andmoveable plunger head of the delivery device of FIG. 17.

FIG. 19 shows a cross-sectional view taken along line 10-10 of FIG. 18.

FIGS. 20 and 21 show schematic views of embodiments of seal arrangementsfor the plunger head within the reservoir of FIGS. 17 and 18.

FIG. 22 shows a perspective view of an embodiment of connection ends ofthe drive linkage and the rotatable shaft of FIGS. 17 and 18.

FIGS. 23 and 24 show partial cross-sectional views of reservoirs anddrive devices for a delivery device according to further embodiments ofthe present invention.

FIG. 25 shows a perspective view of a delivery device containing tworeservoirs that may employ a drive device according to FIGS. 23, 24 or26 or other suitable drive device.

FIG. 26 shows a schematic cross-sectional view of a reservoir and drivedevice for a delivery device according to a further embodiment of thepresent invention.

FIG. 27 shows a schematic view of a delivery device according to afurther embodiment of the present invention.

FIG. 28 shows a schematic side view of an arrangement of a durablehousing portion and a disposable housing portion of a delivery systemaccording to an embodiment of the invention consistent with theembodiment of FIG. 3.

FIG. 29 shows a schematic side view of an arrangement of a durablehousing portion and a disposable housing portion of a delivery systemaccording to another embodiment of the invention.

FIG. 30 shows a partially exploded view of a delivery device accordingto an embodiment of the invention.

FIG. 31 shows a schematic top view of an arrangement of a durablehousing portion and a disposable housing portion of a delivery systemaccording to an embodiment of the invention.

FIG. 32 shows a schematic top view of an arrangement of a durablehousing portion and a disposable housing portion of a delivery systemaccording to another embodiment of the invention.

FIGS. 33-34 each show a perspective view of a connection arrangement fora disposable housing portion and an injection site module.

FIGS. 35 and 36 each show a perspective view of another connectionarrangement for a disposable housing portion and an injection sitemodule.

FIGS. 37-40 each show a perspective view of yet another connectionarrangement for a disposable housing portion and an injection sitemodule.

DETAILED DESCRIPTION

The present invention relates, generally, to delivery devices, systemsand methods for delivering an infusion medium, such as a drug, to arecipient, such as a medical patient-user. In particular embodiments, adelivery device includes a disposable portion that secures to therecipient and that may be readily disposed of after it has been in usefor a period of time. Such embodiments may be configured to provide areliable, user-friendly mechanism to secure the delivery device to apatient-user for delivery of a fluidic infusion medium to thepatient-user.

While embodiments of the present invention are described herein withreference to an insulin delivery example for treating diabetes, otherembodiments of the invention may be employed for delivering otherinfusion media to a patient-user for other purposes. For example,further embodiments of the invention may be employed for deliveringother types of drugs to treat diseases or medical conditions other thandiabetes, including, but not limited to drugs for treating pain orcertain types of cancers, pulmonary disorders or HIV. Furtherembodiments may be employed for delivering media other than drugs,including, but not limited to, nutritional media including nutritionalsupplements, dyes or other tracing media, saline or other hydrationmedia, or the like. Also, while embodiments of the present invention aredescribed herein for delivering or infusing an infusion medium to apatient-user, other embodiments may be configured to draw a medium froma patient-user.

A generalized representation of an infusion medium delivery system 10 isshown in FIG. 1, wherein the system includes a delivery device 12configured according to an embodiment of the invention described herein.The system 10 may also include other components coupled forcommunication with the delivery device 12, including, but not limitedto, a sensor or monitor 14, a command control device (CCD) 16 and acomputer 18. Each of the CCD 16, the computer 18, the sensor or monitor14 and the delivery device 12 may include receiver or transceiverelectronics that allow communication with other components of thesystem. The delivery device 12 may include electronics and software foranalyzing sensor data and for delivering an infusion medium according tosensed data and/or pre-programmed delivery routines. Some of theprocessing, delivery routine storage and control functions may becarried out by the CCD 16 and/or the computer 18, to allow the deliverydevice 12 to be made with more simplified electronics. However, in otherembodiments, the system 10 may include delivery device 12 that operateswithout any one or more of the other components of the system 10 shownin FIG. 1. Examples of the types of communications and/or controlcapabilities, as well as device feature sets and/or program options maybe found in U.S. patent application Ser. No. 10/445,477 filed May 27,2003, and entitled “External Infusion Device with Remote Programming,Bolus Estimator and/or Vibration Alarm Capabilities,” and U.S. patentapplication Ser. No. 10/429,385 filed May 5, 2003, and entitled“Handheld Personal Data Assistant (PDA) with a Medical Device and Methodof Using the Same,” U.S. patent application Ser. No. 09/813,660 filedMar. 21, 2001, and entitled “Control Tabs For Infusion Devices AndMethods Of Using The Same,” all of which are incorporated herein byreference in their entirety.

In the generalized system diagram of FIG. 1, the delivery device 12 andsensor or monitor 14 are secured to a patient-user 1. The locations atwhich those components are secured to the patient-user 1 in FIG. 1 areprovided only as a representative, non-limiting example. The deliverydevice 12 and sensor or monitor 14 may be secured at other locations onthe patient-user 1, and such locations may depend upon the type oftreatment to be administered by the system 10. Such other locations mayinclude, but are not limited to, other locations on the patient-user'sbody, locations on the patient-user's clothing, belt, suspenders,straps, purse, tote or other structure that may be carried by thepatient-user. Thus, while embodiments are described herein withreference to a patch-like device that secures to the patient-user'sskin, other embodiments may be configured as portable devices that maybe carried by the user, for example, by securing the device to anarticle of the user's clothing or providing additional securingstructure, such as straps, tie strings, or the like, to secure to thepatient-user or the patient-user's clothing or the like.

As described in further detail below, the delivery device 12 contains areservoir of an infusion medium and delivers the infusion medium intothe patient-user's body in a controlled manner. Control instructionsand/or data may be communicated between the delivery device 12, thesensor or monitor 14, the CCD 16 and the computer 18. The deliverydevice 12 may be configured to secure to the skin of a patient-user 1,in the manner of a patch, at a desired location on the patient-user. Insuch embodiments, it is desirable that the delivery device 12 haverelatively small dimensions for comfort and ability to conceal, forexample, under a garment.

Examples of patch-like delivery devices are described in U.S. patentapplication Ser. No. 11/211,095, filed Aug. 23, 2005, which isincorporated herein, in its entirety. A further example of a patch-likedelivery device 12 is shown in FIGS. 2-5 herein. The delivery device 12in FIGS. 2 and 3 includes a first housing portion 20 that, in someembodiments, may be disposable after one or a number of specified uses,and a second housing portion 22 that, in some embodiments, may be adurable housing portion cable of multiple usages. The disposable housingportion 20 may support structural elements that ordinarily contact thepatient-user's skin or the infusion medium, during operation of thedelivery device 12. On the other hand, the durable housing portion 22may support elements (including electronics, motor components, linkagecomponents, and the like) that do not ordinarily contact thepatient-user or the infusion medium during operation of the deliverydevice 12. Thus, elements in the durable portion 22 of the deliverydevice 12 are typically not contaminated from contact with thepatient-user or the infusion medium during normal operation of thedelivery device 12.

In the illustrated embodiment, the disposable portion 20 of the deliverydevice 12 includes a base 21 that includes or otherwise supports areservoir retaining portion 24 that houses a reservoir. The durableportion 22 may include a housing that secures onto the base 21 adjacentthe reservoir retaining portion 24. The durable portion 22 may house asuitable drive device, such as an electrically operated motor (not shownin FIGS. 2 and 3), and drive linkage components (not shown in FIG. 2)for driving fluid out of the reservoir. The durable portion 22 also mayhouse suitable control electronics (not shown in FIGS. 2 and 3) forcontrolling the operation of the drive device to drive fluid from thereservoir in a controlled manner. Further embodiments may includecommunication electronics (not shown in FIGS. 2 and 3) within thedurable portion 22, for communicating with the sensor or monitor 14, theCCD 16, the computer 18 and/or other components of the system 10 shownin FIG. 1.

The base 21 of the disposable housing portion 20 has a bottom surface(facing downward and into the page in FIGS. 2 and 3) that is configuredto secure to a patient-user's skin at a desired location on thepatient-user. A suitable adhesive may be employed at the interfacebetween the bottom surface of the base 21 and the patient-user's skin,to adhere the base 21 to the patient-user's skin. The adhesive may beprovided on the bottom surface of the base portion 21, with a peelablecover layer 23 covering the adhesive material. In this manner, apatient-user may peel off the cover layer 23 to expose the adhesivematerial and then place the adhesive side of the base 21 against thepatient-user's skin.

The disposable portion 20 may include a button or other operator 25 foroperating a needle inserter device located within the reservoirretaining portion 24. Alternatively, or in addition, reference number 25may represent an opening, through which an external needle inserterdevice may operate. Alternatively, or in addition to an operator oropening 25, the needle inserter device may be activated, through awireless link, from an external controller, such as the CCD 16, sensoror monitor 14 or computer 18. For such embodiments, the CCD 16, sensoror monitor 14 or computer 18 includes a wireless signal transmitter,while the delivery device includes a receiver for receiving a wirelessactuation signal and an electronic actuator that is controlled toactuate the needle inserter device, upon receipt of an actuation signalfrom the CCD 16, sensor or monitor 14 or computer 18. Examples ofsuitable needle inserter device are described in U.S. patent applicationSer. No. 11/211,095, filed Aug. 23, 2005, and U.S. Patent ApplicationNo. 60/839,840, titled INFUSION MEDIUM DELIVERY SYSTEM, DEVICE ANDMETHOD WITH NEEDLE INSERTER AND NEEDLE INSERT DEVICE AND METHOD, filedAug. 23, 2006, (attorney docket no. 047711-0384), each of which isincorporated herein by reference in its entirety. Other needle/cannulainsertion tools may be used (or modified for use) to insert a needleand/or cannula, such as for example U.S. patent application Ser. No.10/389,132 filed Mar. 14, 2003, and entitled “Auto Insertion Device ForSilhouette Or Similar Products,” and/or U.S. patent application Ser. No.10/314,653 filed Dec. 9, 2002, and entitled “Insertion Device ForInsertion Set and Method of Using the Same,” both of which areincorporated herein by reference in their entirety. Alternatively, thereservoir retaining portion may include a suitable opening or port forconnecting one end of a hollow tube to the reservoir, while the otherend of the hollow tube is connected to a hollow needle for piercing thepatient-user's skin and conveying the infusion medium from the reservoirinto the patient-user, for example, as described with reference to FIG.2 of U.S. patent application Ser. No. 11/211,095, filed Aug. 23, 2005and/or as described herein with reference to FIG. 29.

The durable portion 22 of the delivery device 12 includes a housingshell configured to mate with and secure to the disposable portion 20.The durable portion 22 and disposable portion 20 may be provided withcorrespondingly shaped grooves, notches, tabs or other suitable featuresthat allow the two parts to easily snap together, by manually pressingthe two portions together in a manner well known in the mechanical arts.In a similar manner, the durable portion 22 and disposable portion 20may be separated from each other by manually applying sufficient forceto unsnap the two parts from each other. In further embodiments, asuitable seal, such as an o-ring seal, may be placed along theperipheral edge of the disposable portion 20 and/or the durable portion22, so as to provide a seal against water between the disposable portion20 and the durable portion 22.

The durable portion 22 and disposable portion 20 may be made of suitablyrigid materials that maintain their shape, yet provide sufficientflexibility and resilience to effectively snap together and apart, asdescribed above. The base 21 material may be selected for suitablecompatibility with the patient-user's skin. For example, the disposableportion 20 and the durable portion 22 of the delivery device 12 may bemade of any suitable plastic, metal, composite material or the like. Thedisposable portion 20 may be made of the same type of material or adifferent material relative to the durable portion 22. The disposableportion and durable portions may be manufactured by injection molding orother molding processes, machining processes or combinations thereof.

The base 21 of the disposable housing portion 20 may be made of arelatively flexible material, such as a flexible silicone, plastic,rubber, synthetic rubber or the like. By forming the base 21 of amaterial capable of flexing with the patient-user's skin, a greaterlevel of patient-user comfort may be achieved when the base is securedto the patient-user's skin. Also, a flexible base 21 can result in anincrease in the site options on the patient-user's body at which thebase 21 may be secured.

The disposable portion 20 and/or the durable portion 22 may include aninternal sensor (not shown in FIGS. 2 and 3) for connection to apatient-user, for example, through a needle (not shown in FIGS. 2 and 3)or a set of micro-needles for piercing a patient-user's skin when thedisposable portion 20 is secured to a patient-user's skin. In suchembodiments, a suitable aperture (not shown in FIGS. 2 and 3) may beformed in the base 21, to allow the passage of the sensor needle ormicro-needles, when the sensor needle is extended to pierce apatient-user's skin. Alternatively, or in addition, micro-needles may bearranged on or through the adhesive material on the base 21, to passthrough the patient-user's skin, when the base 21 is adhered to thepatient-user's skin. Alternatively, the durable portion 22 of thedelivery device 12 may be connected to an external sensor 14, through asensor lead, as described in U.S. patent application Ser. No.11/211,095, filed Aug. 23, 2005. The sensor may include any suitablebiological sensing device, depending upon the nature of the treatment tobe administered by the delivery device 12. For example, in the contextof delivering insulin to a diabetes patient-user, the sensor 14 mayinclude a blood glucose sensor. Alternatively, or in addition, one ormore environmental sensing devices may be included in or on the deliverydevice 12, for sensing one or more environmental conditions. In furtheralternatives, the sensor may be included with as a part or along sidethe infusion cannula and/or needle, such as for example as shown in U.S.patent Ser. No. 11/149,119 filed Jun. 8, 2005, and entitled “DualInsertion Set,” which is incorporated herein by reference in itsentirety.

As described above, by separating disposable elements of the deliverydevice 12 from durable elements, the disposable elements may be arrangedon the disposable portion 20, while durable elements may be arrangedwithin a separable durable portion 22. In this regard, after one (or aprescribed number) of uses of the delivery device 12, the disposableportion 20 may be separated from the durable portion 22, so that thedisposable portion 20 may be disposed of in a proper manner. The durableportion 22 may, then, be mated with a new (un-used, user-filled,pre-filled, refurbished, refilled or re-manufactured) disposable portion20 for further delivery operation with a patient-user.

A reservoir 26 may be supported by the reservoir retaining portion 24 ofthe disposable portion 20 in any suitable manner. The reservoir 26 maybe a hollow internal volume of the reservoir retaining portion 24, suchas, but not limited to, a cylindrical-shaped volume as shown in brokenlines in FIG. 3. Alternatively, the reservoir 26 may be a cartridge orgenerally cylindrical canister having a shape and size to be receivedwithin a hollow internal volume of the reservoir retaining portion. Thereservoir 26 is configured for containing a fluidic infusion medium.

The reservoir 26 has a port and a septum. The septum is located in aposition at which a hollow needle or cannula may pass through the septumand into a patient-user's skin, when the disposable housing portion 20is secured to a patient-user's skin, as described below. In otherembodiments, the port and septum of the reservoir 26 may be connectableto a patient-user, through an external needle or cannula, through aconnector and external tubing, as shown in FIG. 2 of U.S. patentapplication Ser. No. 11/211,095, filed Aug. 23, 2005, for providing afluid flow path between the reservoir 26 and the patient-user, when thedisposable housing portion 20 is secured to a patient-user's skin. Infurther embodiments, the port or septum may be used (alternatively or inaddition to an outlet port) for filling or re-filling the reservoir 26,for example, but not limited to, inserting a syringe through the septumand passing fluid from the syringe into the reservoir. Examples ofneedle/septum connectors can be found in U.S. patent application Ser.No. 10/328,393 filed Dec. 22, 2003, and entitled “Reservoir Connector,”which is incorporated herein by reference in its entirety. In otheralternatives, non-septum connectors such as Luer locks, or the like maybe used.

The durable portion 22 of the delivery device 12 may include a motor orother force-applying mechanism, for applying a force to the infusionmedium within the reservoir 26 to force the fluidic infusion medium outof the reservoir 26 and into the hollow needle or cannula (not shown inFIGS. 2 and 3), for delivery to the patient-user. For example, anelectrically driven motor may be mounted within the durable portion 22with appropriate linkage for causing the motor to operably connect to(through the linkage) a piston plunger within the reservoir and drivethe piston plunger in a direction to force the fluidic infusion mediumout of the reservoir port and into the patient-user. The motor may bearranged within the durable portion 22 and the reservoir 26 may becorrespondingly arranged on the disposable portion 20, such that theoperable connection of the motor with the reservoir piston (e.g.,through appropriate linkage) occurs automatically upon the patient-usersnap fitting the durable portion 22 onto the disposable portion 20 ofthe delivery device 12.

One example of a motor and reservoir configuration is shown in FIG. 4.In the embodiment of FIG. 4, the reservoir 26 (shown in cross-section)is a canister, for example, made of a suitable metal, plastic, ceramic,glass, composite material or the like, and having a hollow interior 28for containing a fluidic infusion medium. For example, the canister maybe formed of a plastic material referred to as TOPAS (trademark ofTicona, a subsidiary of Celanese Corporation), such as described in U.S.patent application Ser. No. 11/100,188, filed Apr. 5, 2005 (PublicationNo. 2005/0197626), the contents of which is incorporated herein in itsentirety.

The canister reservoir 26 in FIG. 4 may be configured to fit within andbe removable from a correspondingly-shaped opening and volume in thereservoir retaining portion 24 shown in FIG. 3. In such embodiments, thecanister reservoir 26 and reservoir retaining portion 24 may include oneor more mating protrusions, grooves, indentations and/or non-circularcross-section that restrain the canister reservoir 26 from rotatingabout the axis A relative to the reservoir retaining portion 24, oncethe canister reservoir 26 is fitted within the reservoir retainingportion 24. In further embodiments, a canister reservoir 26 may bepermanently fixed within the interior volume of the reservoir retainingportion 24.

By supporting a canister reservoir 26 in a manner that allows thereservoir 26 (and piston plunger 32) to be removed and replaced relativeto the remainder of the disposable portion 20, a user may replace aspent canister reservoir 26 with a new (un-used, user-filled,pre-filled, refurbished, refilled or re-manufactured) canister reservoir26 (and piston plunger 32), while the disposable portion remains securedto the patient-user's skin (or otherwise secured to or carried by thepatient-user, in contexts in which the housing portions do not adhere tothe patient-user's skin). In this manner, the same disposable portion 20may be used for multiple new reservoirs 26 and, then, disposed of aftera prescribed number of unused new, re-filled, user-filled, pre-filled,refurbished or re-manufactured reservoirs have been used on thedisposable portion 20, while the same durable portion 22 may be used formultiple disposable portion 20 replacements. This also provides the userwith the option to change medication delivery, by changing out andreplacing reservoirs 26 with different ones containing either differentmedications, such as Amilyn, GLP-1, Byetta, Peptide C, insulinsensitizers, combinations of medications (with or without insulin) orthe like. Alternatively, the user my change out different types ofinsulin (e.g., long acting, fast acting, or the like) or utilizedifferent concentrations (U50, U100, U200, U400 or the like).

As described above, in yet further embodiments, the reservoir 26 may beformed unitarily with the reservoir retaining portion 24, for example,as a shaped, hollow interior of the reservoir retaining portion 24. Insuch embodiments, the hollow interior of the reservoir retaining portion24 may be coated or otherwise lined with a suitable metal, plastic,plastic, TOPAS (trademark of Ticona, a subsidiary of CelaneseCorporation), ceramic, glass, composite material or the like.Alternatively, or in addition, the retaining portion 24, itself, may bemade of a suitable metal, plastic, plastic, TOPAS (trademark of Ticona,a subsidiary of Celanese Corporation), ceramic, glass, compositematerial or the like.

The reservoir 26 includes a septum 30 that can be pierced by a hollowneedle or cannula to provide a hollow flow path from the interior 28 ofthe reservoir 26 to the patient-user. Examples of mechanisms that may beused for moving a hollow needle through a septum of a reservoir aredescribed in U.S. patent application Ser. No. 11/211,095, filed Aug. 23,2005, and U.S. Patent Application No. 60/839,840, titled INFUSION MEDIUMDELIVERY SYSTEM, DEVICE AND METHOD WITH NEEDLE INSERTER AND NEEDLEINSERT DEVICE AND METHOD, filed Aug. 23, 2006, (attorney docket no.047711-0384). Alternatively, or in addition, the septum 30 may include asurface that is exposed through a wall of the reservoir retainingportion, for refilling the reservoir 26 or withdrawing infusion mediumfrom the reservoir 26, for example, by piercing the exposed surface ofthe septum with a syringe, hollow needle or cannula. The septum 30 maybe formed of a suitable material, such as, but not limited to, rubber,silicone rubber, polyurethane or other materials that may be pierced bya needle and form a seal around the needle. Examples of needle/septumconnectors can be found in U.S. patent application Ser. No. 10/328,393filed Dec. 22, 2003, and entitled “Reservoir Connector,” which isincorporated herein by reference in its entirety. In other alternatives,non-septum connectors such as Luer locks, or the like may be used.

With reference to FIG. 5, the septum 30 may be configured such that ahollow needle or cannula 100 may be passed through the septum to createa fluid flow path between the interior 28 of the reservoir 26 and apatient-user 1. In particular, when the hollow needle or cannula 100 ispassed through the septum 30, a side opening 104 in the hollow needle orcannula 100 may be aligned with a channel or indentation 31 in theseptum 30 to form a fluid flow path between the hollow interior of theneedle and the interior 28 of the reservoir 26. The hollow needle orcannula 100 includes a patient-end opening 106, to form a fluid flowpath between the hollow interior of the needle or cannula 100 and apatient-user 1, upon the sharp end of the needle or an open end of thecannula being inserted in a patient-user's skin. Alternatively, aninjection site for inserting a hollow needle or cannula into apatient-user and coupling the needle or cannula in fluid flowcommunication with the reservoir, as described below with reference tothe injection site 132 in FIG. 15, may be employed in the embodiment ofFIGS. 1-5. In further embodiments, the injection site may comprise a setof hollow micro-needles arranged to pierce a patient-user's skin, whenthe disposable housing portion 20 is secured to the patient-user's skin,wherein the micro-needles are connected in fluid-flow communication (forexample, through a manifold structure) to the reservoir 26.

Referring again to FIG. 4, a piston plunger 32 is moveable within theinterior of the reservoir, for changing the volume of thefluid-containing portion of the interior 28 of the reservoir 26. When ahollow needle or cannula is passed through the septum 30 (or a set ofmicro-needles are arranged in fluid flow communication with thereservoir) to form a fluid flow path from the reservoir to apatient-user, as described herein, infusion medium inside of thereservoir 26 may be expelled from the reservoir, into the patient-user,in response to a force applied by the piston plunger 32.

The piston plunger 32 extends partially into the interior of thereservoir 26 from the opposite side of the canister relative to theseptum 30. The piston plunger 32 may be made of a suitably rigidmaterial, such as but not limited to metal, plastic, ceramic, glass orcomposite material, and has a head 34 that has an outside diameter ofslightly less than the inside diameter of the interior 28 of thereservoir 26. Alternatively, the piston plunger 32 may be made of acompressible material (such as, but not limited to, an elasticallycompressible plastic, rubber, silicone, or the like) and may be slightlylarger in diameter than the inside diameter of the interior 28 of thereservoir 26, so as to be compressed sufficiently to fit within theinterior 28 of the reservoir 26. One or more seals, such as but notlimited to o-ring type seals 36, may be arranged within annular groovesprovided on the piston plunger head 34. The o-ring seals 36 may be madeof any suitable material, including, but not limited to rubber, plastic,metal, composite material or the like, where such o-rings provide asealing function for inhibiting the leakage of infusion medium from thepiston-plunger end of the reservoir 26. The materials from which thecanister portion of the reservoir 26, piston plunger 32 and seal(s) 36are made are preferably selected for suitable strength and durabilitycharacteristics, as well as compatibility with the infusion medium.Examples of potential piston plunger configurations may be found in U.S.Pat. No. 6,817,990 issued Nov. 16, 2004, and entitled “Improved FluidReservoir Piston,” which is incorporated herein by reference in itsentirety.

The piston plunger 32 and the interior surface of the reservoir 26 mayinclude an anti-rotation structure, such as, but not limited to, one ormore mating protrusions, grooves, indentations similar to thosedescribed below with respect to FIG. 17 and/or non-circularcross-section that restrain the piston plunger 32 from rotating aboutthe axis A relative to the reservoir 26. Alternatively, theanti-rotation feature may include one or more seals, such as the seal(s)36, provided that such seal(s) have sufficient frictional resistancewith the interior surface of the reservoir 26 to inhibit rotation of thepiston plunger 32 about the axis A, relative to the reservoir 26. Forembodiments in which one or more protrusions and mating grooves areprovided on the piston plunger 32 and interior surface of the reservoir26, the protrusions and grooves may be formed with sufficiently slowlyarched or curved surfaces (instead of abrupt angles or corners), toallow a seal to be readily placed over the surfaces and seal against thepiston plunger 32 and interior surface of the reservoir 26. In yetfurther embodiments, an anti-rotation structure may be provided on thepiston shaft 40 and may include any suitable structure for engaging asurface of the durable housing portion 22 or disposable housing portion20 (or other suitable surface structure supported by the durable housingportion 22 or the disposable housing portion 20) and inhibiting rotationof the piston shaft 40 about the axis A.

The piston plunger 32 in FIG. 4 includes an engagement portion 38,located external to the interior 28 of the reservoir 26 and connected bya plunger shaft 40 to the plunger head 34. The piston plunger 32 isconfigured to be moveable in the axial direction A of the reservoir 26.The fluid-containing portion of the interior volume 28 of the reservoir26 varies, with movement of the piston plunger 32 in the axial directionA of the reservoir 26. The engagement portion 38 is provided with keys,key slots or threads 39 (hereinafter referred to as threads) that areconfigured to operatively engage corresponding key slots, keys orthreads (hereinafter, referred to as threads) on a lead shaft 42. Asdescribed in more detail below, when the engagement portion 38 isoperatively engaged with the lead shaft 42 and a drive motor 44 rotatesthe lead shaft 42, the piston plunger 32 will move axially within thereservoir 26.

The anti-rotation structure described above inhibits the piston plunger32 from rotating about the axis A. Accordingly, the piston plunger 32may be arranged in, and inhibited from rotating away from, a position inwhich the threaded surface 39 of the engagement portion 38 faces adirection that allows the surface 39 to automatically align with andreadily come into operable engagement with the lead shaft 42 when thedurable portion 22 and the disposable portion 20 are arranged togetherfor coupling.

The lead shaft 42 may be supported for rotation on the durable portion22 of the delivery device 12. For example, one or more bearings or othersuitable structure may be fixed in the durable portion for supportingthe lead shaft 42 for rotation about its longitudinal axis. In theembodiment of FIG. 4, the lead shaft 42 is supported at two locations bytwo rotary bearings 43 a and 43 b. In other embodiments, the lead shaft42 may be supported in more than two locations by more than two bearingsor may be supported in a cantilevered fashion at one location by asingle bearing 43 a or 43 b. A portion of the length of the lead shaft42 may be exposed for engagement with the engagement portion 38 of thepiston plunger 32. The lead shaft 42 extends through an opening in thedurable portion 22 such that a further portion of the lead shaft 42 islocated within the enclosed interior 54 of the durable portion 22, forengagement with drive linkage, as described below. One or more seals 45may be located around the lead shaft 42, between the exposed portion ofthe lead shaft and the further portion of the lead shaft located in thedurable portion 22. In this manner, the seal(s) 45 may inhibit fluidfrom entering the opening in the durable portion 22 through which thelead shaft 42 extends. The seal(s) 45 may be made of any suitable sealmaterial, including, but not limited to silicone or other flexibleplastic, metal, ceramic, composite material or the like. In furtherembodiments, the seal(s) 45 may comprise a material and/or sealconfiguration that provides a liquid-tight seal, but allows the passageof air to allow equalization of pressure between the interior 54 of thedurable housing portion 22 and the environment exterior of the durablehousing portion 22. In yet other embodiments, a pressure equalizationport opening may be provided in any suitable location of the durablehousing portion, to provide air-flow communication between the interior54 and exterior of the durable housing portion. In such embodiments, theair-flow communication port may be covered with a material that allowsthe passage of air, but inhibits the passage of water or other liquids.Examples of structures that permit air-flow, but that inhibit fluids canbe found in U.S. patent application Ser. No. 10/328,393 filed Dec. 22,2003, and entitled “Reservoir Connector,” and U.S. patent applicationSer. No. 10/699,429 filed Oct. 31, 2003, and entitled “External InfusionDevice with a Vented Housing,” both of which are incorporated herein byreference in their entirety.

A drive motor 44 is mechanically coupled to the lead shaft 42, to drivethe lead shaft in a rotary motion about its longitudinal axis, in acontrolled manner. The motor 44 may be coupled to the lead shaft 42through one or more suitable gears, belts, chains, drive shafts or otherlinkage structure. The linkage structure may be configured to provide atorque conversion, for example, to increase torque and decreaserotational speed at the lead shaft, relative to the torque and speedoutput of the motor 44. Accordingly, the motor 44 may produce relativelyhigh-speed rotational motion, which may be converted through the linkagestructure to a lower speed of rotation, but higher torque applied to thelead shaft.

In the embodiment illustrated in FIG. 4, the motor 44 includes a drivegear 46, while the shaft 42 is provided with an engagement gear 47. Alinking gear 48 is arranged between the drive gear 46 and the engagementgear 47, to convey rotary drive force from the motor 44 to the shaft 42.The linking gear 48 in FIG. 4 includes hub portion 49 for engaging thedrive gear 46, and a main portion 50 for engaging the engagement gear47. The hub portion 49 is fixed to the main portion 50 and has a smallerdiameter than the main portion 50.

In other embodiments, a linking gear 48 may be arranged such that asmaller diameter hub portion engages the engagement gear 47, while alarger diameter main portion engages the drive gear 46. In yet furtherembodiments, additional gears may be interposed between some or each ofthe gears 46, 47 and 48, to convey rotational motion from the motor 44to rotational motion of the lead shaft 42. In yet further embodiments,the linking gear 48 may be eliminated and the drive gear 46 may bearranged to directly engage the engagement gear 47. In yet furtherembodiments, other linkage structure may be employed to operatively linkthe motor 44 to the lead shaft 42. Further examples of linkage andcontrol structures may be found in U.S. patent application Ser. No.09/813,660 filed Mar. 21, 2001, and entitled “Control Tabs For InfusionDevices And Methods Of Using The Same,” which is incorporated herein byreference in its entirety.

FIGS. 6 and 7 shows a further example embodiment of delivery devicehaving a piston plunger 32, lead shaft 42 and reservoir 26, similar topiston plunger, lead shaft and reservoir described above with respect toFIG. 4. Referring to FIGS. 6 and 7, the reservoir 26 may be arranged ina first or disposable housing portion 20 (similar to the disposablehousing portion described above), while the lead shaft 42 may besupported by the second or durable housing portion 22 (similar to thedurable housing portion described above). In the embodiment in FIGS. 6and 7, the piston plunger 32 has a piston head 34 located within thereservoir 26 and a piston shaft 40 that extends from the peripheral edgeof the piston head 34 to a location outside of the reservoir 26. One ormore seals 36 (for example, similar to seals 36 described above) may beincluded around the outer peripheral surface of the piston head 34, forsealing against the interior surface of the reservoir 26. A partial-nutengagement portion 38 is provided with threads 39 on a arched surface.The arched surface of the engagement portion 38 curves around thelongitudinal axis of the lead shaft 42 to allow the threads 39 toreadily operatively engage with threads on the lead shaft 42 as apartial nut (threading partially, but not fully around the shaft), whenthe disposable housing portion 20 and the durable housing portion 22 areengaged. The arched or curved surface of the threads 39 on theengagement portion 38 allow the engagement portion 38 to easily fit overa portion of the lead shaft 42 and operatively engage the threads on thelead shaft 42 by simply bringing the disposable housing portion 20 andthe durable housing portion 22 together in operative engagement.

In FIG. 6, the disposable housing portion 20 and the disposable housingportion 22 are shown as being separated (for example, just before thedisposable housing portion 20 and the durable housing portion 22 arebrought together for operative engagement). In FIG. 7, the disposablehousing portion 20 and the durable housing portion 22 are engaged, suchthat the threads on the engagement portion 38 on the piston plunger 32is operatively engaged with the threads on the lead shaft 42. The pistonplunger 32, including the piston head 34, the piston shaft 40 and theengagement portion 38 may be configured as a single, unitary member, forexample, by molding, machining, or other suitable manufacturingtechnique, for example, for cost-efficiency. Alternatively, the pistonplunger 32 may be configured as a multi-piece member that is assembledto form a piston plunger 32.

An example embodiment of a motor 44 and linkage structure foroperatively coupling the motor 44 to the lead shaft 42 is shown in FIGS.8, 9 and 10, where FIG. 9 is a view of the structure of FIG. 8, asviewed from the left side of FIG. 8. Similarly, FIG. 10 is a view of thestructure of FIG. 8, as viewed from the right side of FIG. 8. (Theorientation of the linkage gears and motor relative to the lead shaft inFIG. 8 is shown as an opposite or a mirror-image of the orientationshown in FIG. 4, but otherwise is structurally similar to thearrangement in FIG. 4.) In the embodiment of FIGS. 8, 9 and 10, one ormore of the motor and the linkage structure may be provided with ananti-reverse rotation structure, to inhibit rotation of the lead screwin a direction opposite to the normal drive direction (e.g., opposite tothe direction at which the piston plunger is moved to force fluid out ofthe reservoir). Such anti-reverse rotation structure may include aratchet wheel and stop surface arrangement.

For example, in the embodiment of FIGS. 8, 9 and 10, the motor 44 isprovided with a motor escapement wheel 61 on a common motor drive shaftas the drive gear 46 of the motor. The escapement wheel 61 may includeratchet teeth arranged to ride over a stop surface 63 when theescapement wheel is rotated in the normal drive direction, but that abutthe stop surface and inhibit rotation of the motor drive shaft in adirection opposite to the normal drive direction. In a furtherembodiment, an escapement wheel may be provided in the linkagestructure, such as on a common rotary shaft as one of the gears in thelinkage structure. In the embodiment in FIGS. 8, 9 and 10, a secondescapement wheel 67 is provided on the same rotary shaft of the leadshaft gear 47. A stop surface 73 is arranged relative to the escapementwheel 67 to allow the ratchet teeth on the escapement wheel 67 to rideover the stop surface 73, when the lead shaft 42 is rotated in a normaldrive direction, but inhibit rotation of the escapement wheel in adirection opposite to the normal drive direction.

The anti-reverse rotation structure may be provided to inhibitun-intended reverse movement of the piston plunger within the reservoir,for example, due to an improperly aligned motor poles, improper handlingof the lead shaft, or the like. A rotation sensor may be associated witheither one or both of the escapement wheels 61 and 67. In the embodimentof FIGS. 8, 9 and 10, a rotation sensor in the form of a sensor 75 isarranged adjacent the escapement wheel 61 to sense rotation of theescapement wheel 61. The sensor 75 may be any suitable rotation sensorincluding, but not limited to an optical sensor for sensing opticalelements (reflecting or non-reflecting surface features) on theescapement wheel 61, as the wheel 61 is rotated.

In FIGS. 4 and 6-10, the drive gear 46, the linking gear 47 andengagement gear 48 form a gear train for transferring motor drive forcefrom the motor 44 to the lead shaft 42. In this manner, as the motorrotatably drives the motor drive shaft, the gear train transfers themotor drive force to rotate the lead shaft 42. When the piston plunger32 is engaged with the lead shaft 42, rotation of the lead shaft 42causes the engagement portion 38 of the piston plunger 32 to ride alonga portion of the threaded length of the lead shaft 42. In this manner,the rotation of the lead shaft 42 is transferred to an axial movement ofthe piston plunger 32, when the piston plunger is engaged with the leadshaft 42. The available length of travel of piston plunger 32 isdependant upon the length of the threaded portion of the lead shaft 42,the length of the piston plunger shaft 40 and the starting location ofthe engagement portion 38 of the piston plunger along the threadedlength of the lead shaft 42.

The lead shaft 42 may be provided with threads along most or all of thelength of the exposed portion of the shaft, to allow operable engagementof the threads on the engagement portion 38 to the corresponding threadson the lead shaft 42 at any location along the length of the exposedportion of the lead shaft 42. As described above, to further assist theoperable engagement of the threads on the engagement portion 38 to thecorresponding threads on the lead shaft 42, the engagement portion 38may be provided with an arcuate surface on which the threads arearranged. The threaded arcuate surface of the engagement portion 38 mayextend around one half or less (180 degrees or less) of thecircumference of the lead shaft 42, when the engagement portion 38 isengaged with the lead shaft 42, i.e., when the durable housing portionand disposable housing portion are engaged as shown in FIG. 2. Infurther embodiments, the threaded arcuate surface of the engagementportion 38 may extend around a little more than one half (more than 180degrees) of the circumference of the lead shaft 42 and may be composedof sufficiently resilient, flexible material to provide a snap-fit withthe lead shaft, when the engagement portion 38 is engaged with the leadshaft 42, i.e., when the durable housing portion and disposable housingportion are engaged as shown in FIG. 2. Other types of drive engagementstructures that may be used are shown in U.S. patent application Ser.No. 10/379,627 filed Mar. 5, 2003, and entitled “Leadscrew DrivenSyringe With Integral Plunger Nut,” and U.S. Pat. No. 5,954,697 issuedSep. 19, 1999, and entitled “Threaded Nut Syringe Plunger For Use With AMedication Infusion Pump,” both of which are incorporated herein byreference in their entirety.

In other embodiments as represented in FIG. 11 a, the piston plungershaft 40 may be provided with teeth (or threads) along its length andthe lead shaft 42 may have a disk-shaped threaded head portion 41 thatmay be relatively short in length in the axial direction A. The threadedhead portion 41 has threads on its outer peripheral surface to engagethe teeth (or threads) of the piston plunger shaft 40, for example, in arack and pinion type of an arrangement, wherein the piston plunger shaft40 may include a toothed rack and the threaded head portion 41 mayfunction as a pinion gear. In embodiments as shown in FIG. 11 b, thepiston plunger shaft 40 may be provided with an arcuate surface 51 onwhich the teeth (or threads) are located. The arcuate surface 51 extendsalong the longitudinal dimension of the piston plunger shaft 40, outsideof the interior portion of the reservoir and arcs partially around theaxis of the lead shaft 42, to engage the head portion 41, when thedurable housing portion and the disposable housing portion are engagedas shown in FIG. 2. The radius of the arcuate surface 51 may approximatethe radius of the disk-shaped head 41, to allow the head 41 to readily,operatively engage the piston plunger shaft and to increase the surfacearea of engagement between those components, when the durable housingportion and disposable housing portion are engaged as shown in FIG. 2.

Similar to the arcuate surface of the engagement portion 38 in FIG. 4described above, the arcuate surface 51 of the piston plunger shaft 40in FIGS. 11 a and 11 b may extend around one half or less (180 degreesor less) of the circumference of the lead shaft 42, when the pistonplunger shaft 40 is engaged with the lead shaft 42, i.e., when thedurable housing portion and disposable housing portion are engaged asshown in FIG. 2. In further embodiments, the arcuate surface 51 of thepiston plunger shaft 40 may extend around more than one half (more than180 degrees) of the circumference of the lead shaft 42 and may becomposed of sufficiently resilient, flexible material to provide asnap-fit with the lead shaft, when the piston plunger shaft 40 isengaged with the lead shaft 42, i.e., when the durable housing portionand disposable housing portion are engaged as shown in FIG. 2.

In the embodiments of FIGS. 4, 6, 7 and 11 a and 11 b, one of the leadshaft 42 or the piston plunger shaft 40 includes a threaded portionextending a length along the direction of axis A, beyond the length inthe direction of axis A of the fluid containing portion 28 of thereservoir 26. The piston plunger shaft 40 may be provided with threadsalong most or all of the length of the exposed portion of the shaft, toallow operable engagement with the lead shaft 42 or threaded headportion 41, at any location along the length of the exposed portion ofthe piston plunger shaft 40.

A motor 44, lead shaft 42 and any linkage between the motor and leadshaft may be supported by the durable portion 22 of the delivery devicein a location at which the threaded portion of the shaft 42 engages thethreaded portion of the piston plunger 32, as shown in FIGS. 4, 7, 8 or11 a. In this manner, when the durable portion 22 is arranged to besecured (such as by snap fitting, friction fitting or other suitableengagement configuration) onto the disposable portion 20, the threadedportion of the shaft 42 operatively engages the threaded portion of thepiston plunger 32 without requiring further user manipulation of theelements. In other embodiments, additional manipulation of the housingportions and/or a manual operator may be required to operatively engagethe threaded portion of the shaft 42 with the threaded portion of thepiston plunger 32, while or after the durable portion 22 is arranged tobe secured (such as by snap fitting, friction fitting or other suitableengagement configuration) onto the disposable portion 20.

While not shown in FIGS. 4 and 6, the motor 44 may be provided withelectrical terminals for connection to a motor control circuit (e.g.,motor control circuit 52 shown in FIG. 4 or a similar motor controlcircuit, not shown, in the durable housing portion 22 of FIG. 6. Themotor control circuit 52 may be mounted within the durable portion 22 ofthe delivery device, for controlling the operation of the motoraccording to a desired infusion delivery program or profile. A deliveryprogram or profile may be stored within a suitable electronic storagemedium (not shown) located within the durable portion 22 and/or may becommunicated to the delivery device 12 from other sources, such as a CCD16 or a computer 18 (as shown in FIG. 1). In such embodiments, thedelivery program or profile may be employed by the motor control circuit52 to control the operation of the motor 44 in accordance with thedelivery program or profile. Alternatively or in addition, the motorcontrol circuit 52 may control the motor 44 to deliver one or morediscrete volumes of infusion medium in response to delivery demandcontrol signals generated within the device 12 or communicated to thedevice 12 from other sources, such as a CCD 16, sensor or monitor 14 ora computer 18 (as shown in FIG. 1).

The durable portion 22 may contain additional electronic circuitry (notshown) for communication with external devices such as the CCD 16 orcomputer 18, for storage of sensor data or other data, for processingand control functions, or for other functions. The durable portion 22may have a user interface (not shown) including one or more buttons,electronic display (including, but not limited to, an LED display, anLCD display or other suitable electronic display), or the like, to allowa user to access data and/or input data or instructions to controlelectronic circuitry within the durable portion 22. Examples of thetypes of communications and/or control capabilities, as well as devicefeature sets and/or program options may be found in U.S. patentapplication Ser. No. 10/445,477 filed May 27, 2003, and entitled“External Infusion Device with Remote Programming, Bolus Estimatorand/or Vibration Alarm Capabilities,” and U.S. patent application Ser.No. 10/429,385 filed May 5, 2003, and entitled “Handheld Personal DataAssistant (PDA) with a Medical Device and Method of Using the Same,”both of which are incorporated herein by reference in their entirety.

In some embodiments, the durable portion 22 may contain a battery, highenergy capacitor or other electronic power source (not shown) forproviding electrical power to the motor 44, motor control circuit 52 andother electronic circuitry contained in the durable portion 22. In suchembodiments, the battery, high energy capacitor or other electronicpower source may be rechargeable through a recharge connector (notshown) provided on the durable portion 22. In other embodiments, abattery, capacitor or other electronic power source (not shown) may besupported on the disposable portion 20 and connectable to the motor 44,motor control circuit 52 and other electronic circuitry in the durablehousing portion, through electrical connectors that make an electricalconnection upon the durable portion 22 being coupled to the disposableportion 20, without additional manual manipulation. Such electricalconnectors may include one or more pairs of conductive pads, where eachpair of pads is connected to opposite poles of the power source andlocated on any suitable surface of the disposable portion 20 thatengages a corresponding surface on the durable portion 22, when thedurable portion 22 is coupled in engagement with the disposable portion20. In such embodiments, the corresponding surface of the durableportion 22 includes one or more corresponding pairs of conductive padsthat are electrically connected to the motor 44, motor control circuit52 and other electronic circuitry in the durable housing portion and arearranged to engage the conductive pads on the disposable portion, whenthe durable portion 22 is engaged with the disposable portion 20. Inother embodiments, further manual manipulation of the housings and/or amanual operator may be required to complete the electrical connection,once the durable portion 22 and the disposable portion 20 are engaged.

The durable portion 22 includes an interior volume 54 that contains themotor 44, gears 46-48, motor control circuit 52, other electroniccircuitry and, in some embodiments described above, a power source. Toprotect those electrical and mechanical components from certainenvironmental conditions (such as, but not limited to, moisture, air,biological or medical fluids), the interior volume 54 of the durableportion 22 may be suitably sealed from the external environment by thehousing structure 55 that forms the durable portion 22 and the seal(s)45 for the opening through which the lead shaft 42 extends. Accordingly,the housing structure of the durable portion 22 and the seal(s) 45 mayform a suitable moisture-tight seal, air-tight seal and/or hermeticseal, to protect the electronic components located in the interiorvolume 54 and/or separate those components from environmental, medicalor biological materials to which the disposable portion 20 is exposedduring normal operation. The gear train composed of gears 46, 47 and 48,may be included in the sealed interior volume 54, to protect and/orseparate those mechanical components from environmental or biologicalmaterials, as well.

As discussed above, in the arrangement illustrated in FIGS. 2, 3, 4, 6,7 and 11, the durable portion 22 may be attached (for example, snapfitted, friction fitted, or the like) onto the disposable portion 20,where the threaded portion of the lead shaft 42 automatically engagesthe threaded portion of the piston plunger 32 without requiring furtheruser manipulation of the elements. In further embodiments, further usermanipulation may be required for the lead shaft 42 to engage thethreaded portion of the piston plunger 32. In the embodiment of FIGS. 4,6 and 7, the threaded surface 39 of an engagement portion 38 of thepiston plunger 32 may have an arcuate surface that curves around aportion of the longitudinal axis of the lead shaft 42. By providing thesurface of the engagement portion 38 of the piston plunger 32 with anarcuate shape that curves around a portion of the longitudinal axis ofthe lead shaft 42, the surface area of the surface 39 that engages thelead shaft 42 may be increased. In addition, the curvature of thesurface 39 of the engagement portion 38 around a portion of thelongitudinal axis of the lead shaft 42 can help to inhibit inadvertentseparation of the engagement portion 38 and the lead shaft 42, once theengagement portion 38 is engaged with the lead shaft 42. The curvatureof the surface 39 also may allow the engagement portion 38 to easilyalign with and operably engage the lead shaft 42, by bringing the leadshaft 42 into contact with the engagement portion 38 as a consequence ofthe manual operation of coupling the durable portion 22 to thedisposable portion 20.

FIGS. 12-15 show a further example embodiment of a piston plunger 32 andlead shaft 42 configured for operable engagement, upon engagement of thedisposable housing portion 20 and the durable housing portion 22. FIG.12 is a perspective view of an embodiment of a reservoir, piston plungerand lead shaft suitable for the delivery device embodiment of FIG. 4.FIG. 13 is an axial view of the piston plunger of FIG. 12, with the clipopen, while FIG. 14 is an axial view of the piston plunger of FIG. 12,with the clip closed. FIG. 15 is a perspective view of the pistonplunger of FIG. 12 assembled with the reservoir of FIG. 12, and with thelead shaft of FIG. 12 in operable engagement with the piston plunger.

In the embodiment of FIGS. 12-15, the piston plunger 32 includes anoval-shaped piston head 34, having a shape and size for fitting withinthe correspondingly-shaped interior of the reservoir 26. The oval shapeof the piston head 34 and the interior of the reservoir 26 inhibitrotation of the piston head 34 relative to the reservoir 26, when thepiston head 34 is fitted within the interior of the reservoir 26.

The piston plunger 32 in the embodiment of FIGS. 12-15 includes a pistonshaft 40 that has concave surface extending along the axial dimension A,that forms a trough shaped curvature, curving partially around the axisA. The trough-shaped curvature of the piston shaft 40 provides areceptacle for receiving the lead shaft 42, when the disposable housingportion 20 and the durable housing portion 22 are engaged. The pistonshaft 40 includes at least one clip 53, for operatively engaging thelead shaft 42, when the disposable housing portion 20 and the durablehousing portion 22 are engaged. While the embodiment of FIGS. 12-15 isshown with one clip 53, other embodiments may include two or more clipsalong the axial length A of the piston shaft 40.

The clip 53 includes a pair of clip arms 53 a and 53 b, each of whichare flexible and/or pivotal between an open state (shown in FIG. 13) anda closed state (shown in FIG. 14). In the embodiment of FIGS. 12-15, theclip arms 53 a and 53 b each have a pivot point or flexible hingeportion 57 a and 57 b, respectively, to allow the arms 53 a and 53 b topivot about an axis that is substantially parallel to the axis A,between the open and closed states. One or both of the clip armsincludes threads that are of a suitable size and pitch to operativelyengage with the threads on the lead shaft 42. When in an open state,each clip arm 53 a and 53 b has a free end that is spaced apart from thefree end of the other clip arm. When in the closed state (FIG. 14), thefree ends of the clip arms 53 a and 53 b engage and may partiallyoverlap.

The free ends of the clip arms 53 a and 53 b may include lockingstructure for allowing the clip arms to lock together, when the freeends of the clip arms 53 a and 53 b are brought together, by flexing orpivoting the clip arms 53 a and 53 b about the pivot point or flexiblehinge portion 57 a and 57 b, respectively. Such locking structure mayinclude one or more protrusions 59 a and 59 b adjacent the free end ofeach clip arm 53 a and 53 b, respectively, where the protrusions 59 aand 59 b provide stop surfaces that abut each other when the free endsof the clip arms 53 a and 53 b are brought together, with one clip arm(e.g., clip arm 53 b) partially overlapping the other clip arm (e.g.,clip arm 53 a).

In one embodiment, the clip arms 53 a and 53 b are biased (for exampleby a spring or a natural spring force of the material from which theclip arms are made) toward the closed position, but are held in an openposition (as shown in FIG. 13) by a releasable lock mechanism. The lockmechanism may be released, for example, by the action of the lead shaft42 engaging the flexible hinge portion 57 a and 57 b of one or both cliparms 53 a and 53 b. In other embodiments, the lock mechanism may bereleased by a manual operator (not shown), operable from outside of thedisposable housing portion 20 and the durable housing portion 22, whenthose housing portions are engaged. In yet other embodiments, the cliparms 53 a and 53 b may be configured to be in an open position (as shownin FIG. 13) by the natural spring force of the material that forms theclip arms (or by a further bias member, such as a separate spring), andmay be closed by the manual operation of engaging the disposable housingportion 20 with the durable housing portion 22, for example by squeezingthe arms 53 a and 53 b together by sliding the arms in engagement with adiverging pair of walls or other structure in the durable housingportion 22 after the engagement portion 38 of the piston plunger 32 ismanually aligned to engage with the lead shaft 42. In yet otherembodiments, the clip arms 53 a and 53 b may be biased toward a closedposition (by the natural spring force of the arms or by a separate biasmember, such as a spring), while a stop member maintains the arms 53 aand 53 b in an open position (as shown in FIG. 13) prior to assembly ofthe disposable housing portion 20 with the durable housing portion 22.In such an embodiment, a stop release mechanism may be employed torelease the arms 53 a and 53 b from the stop member and allow the arms53 a and 53 b to close around the lead shaft 42, after the engagementportion 38 of the piston plunger 32 is manually aligned to engage withthe lead shaft 42. In such an embodiment, the stop release mechanism maycomprise an automatic structure that moves the stop member (or moves thearms 53 a and 53 b relative to the stop member) to automatically releasethe arms 53 a and 53 b by the manual action of engaging the disposablehousing portion 20 with the durable housing portion 22. Alternatively,the stop release mechanism may comprise a further manual operator thatrequires a further manual operation (pushing a button, moving a lever orthe like) to release the stop member and allow the arms 53 a and 53 b tomove to their closed position.

In operation, as the durable housing portion 22 is manually brought intoengagement with the disposable housing portion 20, the lead shaft 42 onthe durable housing portion is aligned with the axial dimension A of thepiston shaft 40 and is brought into a position between the open cliparms 53 a and 53 b. Either by automatic operation or by manual operationof the clip arms 53 a and 53 b, the clip arms 53 a and 53 b are flexedor pivoted from the open state to the closed state, to operativelyengage the threads on the clip arms with the threads on the lead shaft42, as shown in FIG. 15. Once engaged, rotation of the lead shaft 42causes the piston plunger 32 to move in the axial dimension A, withinthe interior of the reservoir 26.

As described above, when the durable portion 22 and the disposableportion 20 are fitted together with the lead shaft 42 engaging theengagement portion 38 of the piston plunger 32, the motor 44 may becontrolled to rotatably drive the lead shaft 42 and, thus, move thepiston plunger 32 in the axial direction A of the reservoir 26. When theinterior volume of the reservoir 26 is filled with an infusion mediumand a hollow needle or cannula is positioned in a septum of thereservoir (for example, similar to septum 30 discussed above) to form afluid flow path between the reservoir 26 and a patient-user, the pistonplunger 32 may be controlled to move in the axial direction A, towardthe septum 30 end of the reservoir 26, to force infusion medium from thereservoir volume 28, through the hollow needle or cannula and into thepatient-user.

Once the reservoir 26 has been sufficiently emptied or otherwiserequires replacement, the patient-user may simply unsnap and remove thedurable portion 22 from the disposable portion 20 of the delivery device12 and replace the disposable portion 20 (including the reservoir) witha new disposable portion having an unused new, user-filled, prefilled,refurbished, remanufactured or re-filled reservoir 26. The durableportion 22 may be engaged to the new disposable portion and the deliverydevice (including the new disposable portion) may be secured to (orotherwise carried by) the patient-user, as described above.

In further embodiments in which the reservoir 26 includes a reservoircanister that fits within a hollow interior of the reservoir retainingportion 24, the canister may be removed from the retaining portion 24and replaced with an unused new, user-filled, prefilled, refurbished,remanufactured or re-filled canister, to allow the disposable portion 22to remain in place on a patient-user for more than one reservoirdepletion period. In such embodiments, the reservoir canister may bereplaced one or more times during the operable life of the disposableportion 20 and the disposable portion 20 may be removed from thepatient-user and replaced with a new or remanufactured disposableportion 20, for example, after a predefined number of reservoir canisterreplacement operations.

The drive motor 44 in FIG. 4 (or any of the embodiments describedherein) may include any suitable rotary drive device that convertselectrical power to mechanical, rotary motion. Examples of a suitablerotary drive motor 44 include, but are not limited to, a DC motor, flator pancake DC motor, servo motor, stepper motor, electronicallycommutated motor, rotary piezo-electrically actuated motor, and thelike. In further embodiments, the drive motor 44 may include a bender orlinear actuator in combination with an escapement wheel arrangement, torotatably drive the lead shaft 42. For example, a drive device forrotatably driving the lead shaft 42 may include a piezo-electricallyactuated bender and escapement wheel arrangement, a thermally actuatedbender and escapement wheel arrangement, a shape memory alloy wire andescapement wheel arrangement, an electronically actuated solenoid andescapement wheel arrangement, or the like. Examples of shape memoryalloy wire drive systems may be found in U.S. Pat. No. 6,375,638 issuedApr. 23, 2002, and entitled “Incremental Motion Pump Mechanisms Drivenby Shape Memory Alloy Wire or the Like,” and U.S. patent applicationSer. No. 11/230,142 filed Sep. 19, 2005, and entitled “SMA Wire DrivenPositive Displacement MicroPump With Pulsatile Output,” both of whichare incorporated herein by reference in their entirety.

Escapement wheel arrangements operable with bender or linear actuatorsin accordance with example embodiments of the present invention aredescribed with reference to FIGS. 16 a-16 c. As shown in FIG. 16 a, anescapement wheel 60 is supported for rotation around an axis A₁(extending into the page), in the direction of arrow 62. The escapementwheel 60 has an outer peripheral edge provided with serrations or teeth64. Each tooth 64 includes a sloped surface 66 arranged at an obtuseangle relative to an axial direction of the wheel 60 and a catch surface65 in a substantially axial direction of the wheel. A drive pawl 68 islocated adjacent to the escapement wheel 60 and at least partiallybetween two of the teeth on the escapement wheel. The drive pawl 68 issupported for movement in a generally linear direction, as representedby the double arrow 69, between a start position S and an end positionE.

The drive pawl 68 has a drive surface 70 for engaging the catch surface65 of an adjacent tooth 64 on the escapement wheel 60, when the drivepawl 68 is moved in a direction from the start position S to the endposition E. The drive pawl 68 has a further surface 71 facing away fromthe drive surface 70 and configured for riding over the sloping surface66 of a tooth 64 on the escapement wheel 60, when the drive pawl ismoved in a return direction from the end position E to the startposition S. The further surface 71 of the drive pawl 68 may be sloped atan angle relative to the radial direction of drive wheel, to assist thedrive pawl 68 in riding over the sloping surface 66 of a tooth 64 of theescapement wheel.

As described in more detail below, the drive pawl 68 is coupled to abender or linear motion actuator to selectively drive the drive pawl 68from the start position S to the end position E. With each motion of thedrive pawl 68 from the start position S to the end position E, thesurface 70 engages the catch surface 65 of a tooth 64 on the escapementwheel and rotates the escapement wheel 60 a small distance. A biasmember 72 is operably coupled to the drive pawl 68, to bias the drivepawl 68 in a return direction, to return the drive pawl 68 to the startposition. The bias member 72 may include a spring as shown in FIG. 14 aor other suitable mechanism for providing a bias force to return thedrive pawl 68 to the start position, including, but not limited to apermanent magnet, electro-magnet, electronic or thermal linear actuator,shape memory alloy actuator, or the like. In the illustrated embodiment,the bias member 72 is a coil spring having one end coupled to the drivepawl 68 and another end coupled to a fixed surface, for example, a fixedsurface of a wall or other fixed structure of or within the durableportion 22 of the drive mechanism 12 described above.

A further pawl 74 may be provided to inhibit back rotation of theescapement wheel 60 in the direction opposite to the direction of arrow62. For example, the further pawl 74 may be located adjacent theescapement wheel 60 and at least partially between two of the teeth onthe escapement wheel. The further pawl 74 has a surface 76 for engagingthe catch surface 65 of an adjacent tooth 64 on the escapement wheel 60,to inhibit rotary motion of the escapement wheel 60 in the directionopposite to the direction of arrow 62.

The pawl 74 has a further surface 77 facing opposite to the surface 76,configured for riding over the sloping surface 66 of a tooth 64 on theescapement wheel 60, when the escapement wheel is driven in the rotarydirection of arrow 62 by action of the drive pawl 68. The surface 77 ofthe pawl 74 may be angled relative to the radial direction of the drivewheel, to assist the pawl 74 in riding over the sloping surface 66 of atooth 64 of the escapement wheel. The pawl 74 may be supported forpivotal motion about a pivot point 78 in the direction of double arrow79, to allow the surface 77 of the pawl 74 to pivot in a direction awayfrom the escapement wheel, to further assist the pawl 74 in riding overthe sloping surface 66 of a tooth 64 of the escapement wheel.

A bias member 80 may be arranged to bias the surface 76 of the pawl 74toward the escapement wheel, to return the pawl 74 to a position inwhich the surface 76 engages the catch surface 65 of a tooth 64, afterthe pawl 74 has ridden over the sloping surface 66 of an adjacent tooth64 of the escapement wheel. The bias member 80 may include a spring asshown in FIG. 16 a or other suitable mechanism for providing a biasforce to return the pawl 74 to the position in which the pawl surface 76engages the catch surface 65 of a tooth 64, including, but not limitedto a permanent magnet, electro-magnet, electronic or thermal linearactuator, shape memory alloy actuator, or the like. In the illustratedembodiment, the bias member 80 includes a coil spring having one endcoupled to the pawl 74 and another end coupled to a fixed surface, forexample, a fixed surface of a wall or other fixed structure of or withinthe durable portion 22 of the drive mechanism 12 described above. Infurther embodiments, a leaf spring or other suitable spring structuremay be employed, instead of a coil spring. For example, a spring may belocated around or within the pivot point 78 of the pawl 74 for effectingthe bias force described above.

As described above, the drive pawl 68 is coupled to a bender or linearmotion actuator to selectively drive the drive pawl 68 and cause theescapement wheel to rotate a small distance with each motion of thedrive pawl 68 from the start position S to the end position E. A benderor linear actuator may include a piezoelectric bender or piezoelectricactuator, a thermally actuated bender, a shape memory alloy wire, anelectronically actuated solenoid, or the like. Such actuators forproviding small, generally linear movements in response to theapplication of an electrical power signal are known. Examples ofalternative shape memory alloy wire drive systems may be found in U.S.Pat. No. 6,375,638 issued Apr. 23, 2002, and entitled “IncrementalMotion Pump Mechanisms Driven by Shape Memory Alloy Wire or the Like,”and U.S. patent application Ser. No. 11/230,142 filed Sep. 19, 2005, andentitled “SMA Wire Driven Positive Displacement MicroPump With PulsatileOutput,” both of which are incorporated herein by reference in theirentirety.

As shown in FIG. 16 b, a bender actuator 82 may be configured to includea connector end 84 that is provided with a lateral motion represented byarrow 86 relative to a major axis A₂ of the actuator body, when a powersignal is applied to the actuator. Alternatively, as shown in FIG. 14 c,a linear actuator 88 may be configured to include a connector end 90that is provided with a longitudinal motion represented by arrow 92relative to a major axis A₃ of the actuator body, when a power signal isapplied to the actuator. A bender actuator as shown in FIG. 16 b, forproviding lateral motion, may be coupled to the drive pawl 68 at aconnection location 96. The connection location 96 for a bender actuatormay be on a surface of the drive pawl 68 that is substantiallyperpendicular to the drive surface 70. Alternatively, a linear actuatoras shown in FIG. 16 c, for providing longitudinal motion, may be coupledto the drive pawl 68 at a connection location 98. The connectionlocation 98 for a linear actuator may be on a surface of the drive pawl68 that is substantially parallel to the drive surface 70. In thatmanner, a bender or a linear actuator as shown in FIGS. 16 b and 16 cmay be employed to selectively move the drive pawl 68 from the startposition S to the end position E and, thus drive the escapement wheel 60in a rotary manner. In yet further embodiments, the drive pawl 68 may beeliminated and the bender or linear actuator may be arranged to directlyengage the catch surfaces of the teeth on the escapement wheel 60.

The escapement wheel 60 may be configured to rotate the rotary distanceof one tooth for each movement of the drive pawl 68 from the startposition S to the end position E. In further embodiments, the drive pawl68 may be configured to cause the escapement wheel 60 to rotate a rotarydistance of a pre-defined number of teeth greater than one tooth, foreach movement of the drive pawl 68 from the start position S to the endposition E. The escapement wheel 60 may be coupled to the lead shaft 42,to rotate the lead shaft 42 with rotation of the escapement wheel 60. Inone embodiment, the lead shaft 42 may be connected in axial alignmentdirectly to the escapement wheel 60, such that the rotary axis A₁ of theescapement wheel is in alignment with the longitudinal axis of the leadshaft 42. In other embodiments, the escapement wheel 60 may be coupled,in axial alignment, with any one of the drive gear 46, engagement gear47 or linking gear 48 shown in FIG. 4 or FIG. 8, to transfer rotarymotion of the escapement wheel 60 to the lead shaft 42. In yet furtherembodiments, other suitable gear and linkage arrangements may beemployed for transferring rotary motion of the escapement wheel 60 tothe lead shaft 42.

The use of bender or linear actuators with escapement wheel arrangementsas described above may provide certain advantages over electric motorand linkage arrangements, in that the bender or linear actuators canprovide a repeatable, controlled, step-like response to an electricalpower signal. In the context of driving a delivery device for deliveringa medication to a patient-user, the ability to accurately control thedrive response can provide significant advantages, for example, inadministering accurate quantities, small quantities at accurate levelsand accurate recording of delivered quantities of the medication. Inaddition, bender or linear actuators with escapement wheel arrangementscan be made relatively small and flat and can, therefore, improve theability to form the delivery device 12 with a relatively small and flatshape. In addition, bender or linear actuators with escapement wheelarrangements can operate with relatively low power requirements, thusprolonging the operational life of the power source and allowing smallerpower sources to be employed, thus, allowing further reductions in thesize of the delivery device.

Other types of drive devices may be coupled to an escapement wheel 60,as shown in FIG. 16 d, to provide a controlled, step-like response. Forexample, in the embodiment shown in FIG. 16 d, a second wheel 99 has onetooth and is coupled to the lead shaft 42 as described above, while thetoothed escapement wheel 60 is operatively coupled to the lead shaft 42,for example, through a suitable linkage structure as described herein.The second wheel 99 may be driven by any suitable rotary drive source,including, but not limited to a DC motor, flat or pancake DC motor,servo motor, stepper motor, electronically commutated motor, rotarypiezo-electrically actuated motor, and the like. While the second wheel99 in FIG. 16 d is provided with a single tooth to effect a rotation ofthe escapement wheel 60 a rotary distance of a single tooth for eachcomplete rotation of the second wheel 99, other embodiments may employ asecond wheel 99 having two teeth (or another pre-defined number ofteeth) for effecting a rotation of the escapement wheel 60 a rotarydistance of two teeth (or the pre-defined number of teeth) for eachcomplete rotation of the second wheel 99.

The above embodiments involve various manners of conveying a drive forceto the lead shaft 42, to rotate the lead shaft 42 and drive a pistonplunger 32 within the reservoir 26. Further embodiments may employ othermechanisms for driving a plunger within a reservoir, to selectivelydeliver infusion medium from the reservoir.

For example, FIGS. 17-21 show a further embodiment of a delivery device,which includes a disposable portion 120 and a durable portion 122. Thedisposable portion has a reservoir retaining portion 124 in which areservoir 126 is located. The disposable portion 120, durable portion122, reservoir retaining portion 124 and reservoir 126 may be similar tothe disposable portion 20, durable portion 22, reservoir retainingportion 24 and reservoir 26 described above with respect to FIGS. 2-6.However, the reservoir 126 in FIGS. 17-21 employs a rotatable plungershaft 127 located within the reservoir interior 128, instead of thearrangement shown in FIGS. 2-8 that employs a piston plunger shaft 40that extends, lengthwise, a distance beyond the medium-containingportion of the interior 28 of the reservoir 26 by a distance at least asgreat as the distance that the piston head 34 moves over the full periodof use of the reservoir. Accordingly, the overall length of thereservoir and internal shaft of FIGS. 17-21 may be smaller relative tothe overall length of the reservoir and external shaft of FIGS. 2-8, fora given reservoir volume.

The reservoir 126 in FIGS. 17 and 18 may include a septum 130, similarto the septum 30 described above with respect to FIG. 5. The septum 130may include a surface 131 that is exposed through a wall of thereservoir retaining portion 124, for filling the reservoir 126 orwithdrawing infusion medium from the reservoir 26, for example, bypiercing the exposed surface of the septum with a syringe.

An injection site 132 may be located within the disposable portion 120,adjacent the reservoir 126 and connected in fluid flow communication tothe interior of the reservoir 126. The injection site 132 may employ amechanism for inserting a hollow needle or cannula into a patient-user,after the disposable portion 120 is secured to the patient-user andcoupling the needle or cannula in fluid flow communication to theinterior of the reservoir 126. Examples of mechanisms that may be usedfor inserting a hollow needle or cannula into a patient-user andcoupling the needle and cannula in fluid flow communication with areservoir are described in U.S. patent application Ser. No. 11/211,095,filed Aug. 23, 2005, and U.S. Patent Application No. 60/839,840, titledINFUSION MEDIUM DELIVERY SYSTEM, DEVICE AND METHOD WITH NEEDLE INSERTERAND NEEDLE INSERT DEVICE AND METHOD, filed Aug. 23, 2006, (attorneydocket no. 047711-0384). Other needle/cannula insertion tools may beused (or modified for use) to insert a needle and/or cannula, such asfor example U.S. patent application Ser. No. 10/389,132 filed Mar. 14,2003, and entitled “Auto Insertion Device For Silhouette Or SimilarProducts,” and/or U.S. patent application Ser. No. 10/314,653 filed Dec.9, 2002, and entitled “Insertion Device For Insertion Set and Method ofUsing the Same,” both of which are incorporated herein by reference intheir entirety.

The rotatable shaft 127 is threaded along its length within the interiorof the reservoir 126. A moveable plunger head 134 is located within theinterior of the reservoir 126 and is threaded and engaged with therotatable shaft 127. In particular, the plunger head 134 has a threadedchannel that has threads of a pitch and diameter to engage and mate withthe threads of the rotatable shaft 127. By rotating the shaft 127without rotating the plunger head 134, the plunger head is moved alongthe length of the shaft 127, within the interior of the reservoir 126.In this manner, the shaft 127 may be rotated to drive the plunger head134 and force the infusion medium from the reservoir 126 to apatient-user, through a hollow needle or cannula connected in fluid flowcommunication with the reservoir. While the threaded channel in theplunger head 134 may be located at the center of the diameter of theplunger head 134, other embodiments may employ a plunger head 134 withan off-center channel (a channel that is laterally spaced relative tothe longitudinal axis A of the reservoir). An off-center location of thechannel in the plunger head 134 allows the transfer of linear motion(with the rotational motion of the lead shaft 127) to the plunger head134, while inhibiting rotation of the plunger head 134 relative to thelead shaft 127.

One or more seals 136 may be provided around the outer peripheralsurface of the plunger head 134, to inhibit the passage of infusionmedium across the plunger head 134, from the medium-retaining interiorportion 128 of the reservoir to the external side 129 of the plungerhead 134. One or more annular grooves may be provided in the outerperipheral surface of the plunger head 134 for retaining the seal(s)136. The seal(s) 136 may include one or more o-ring seals or othersuitable seal structure and may be made of any suitable seal material,including, but not limited to, rubber, silicone rubber, polyurethane orother plastic material, metal, composite material or the like. Theseal(s) 136 may provide sufficient frictional force between the plungerhead 134 and the interior surface of the reservoir 126 to inhibitrotation of the plunger head 134 with the rotation of the shaft 127.However, in further embodiments, additional structure may be provided toinhibit rotation of the plunger head with the rotation of the shaft 127,including, but not limited to, one or more projections or shapedportions 138 on the plunger head 134 that fit within corresponding oneor more shaped grooves along the length of the interior wall of thereservoir 126, as shown in the cross-section view of FIG. 19 (takenalong the cross-section 19-19 of FIG. 18). The shaped projection(s) 138may have generally curved configurations, with slow curvatures (ascompared to an abrupt step), to allow one or more seals 136 to be placedaround the plunger head. In alternative embodiments, the interior wallof the reservoir 126 may include a projecting portion extending alongthe length of the reservoir, for engaging a corresponding groove in theplunger head 134, similar to, but reverse of the projection and groovearrangement shown in FIG. 19. In yet further alternative embodiments,the cross-sectional shape of the plunger head 134 and the reservoir 126(in the cross-sectional direction shown in FIG. 19) may be non-circular,to inhibit rotation of the plunger head 134 with rotation of the shaft127. Such non-circular cross-section shapes may include, but are notlimited to, an oval or partially oval shape, a polygonal or partiallypolygonal shape, or the like.

The plunger head 134 includes one or more seals 140 arranged to providea fluid-tight seal between the plunger head 134 and the lead shaft 127,to inhibit the passage of infusion medium through the central channel ofthe plunger head 134, from the infusion medium-retaining interiorportion 128 of the reservoir to the external side 129 of the plungerhead 134, as the plunger head 134 is moved toward the septum end of thereservoir 126. The seal(s) 140 may include an annular structure disposedon one side (such as the infusion-medium-contacting side) of the plungerhead 134 and made of any suitable seal material, including, but notlimited to, rubber, silicone rubber, polyurethane or other plasticmaterial, metal, composite material or the like. Alternatively, or inaddition, the seal(s) 140 may be located within the central channel ofthe plunger head 134, between the plunger head 134 and the lead shaft127. In the embodiment of FIG. 20, the lead shaft 127 is, at leastinitially, not threaded, while the plunger head 134 is provided with oneor more cutting blades 145, to cut threads into the lead shaft 127 andride along the cut threads, as the lead shaft is rotated. In theembodiment of FIG. 20, the lead shaft 127 may be made with a smoothsurface and of any suitable material that would allow the thread formingblade(s) 145 to cut threads into the lead shaft 127 when the lead shaft127 is rotated by the drive linkage 154. Rotation of the lead shaft 127would cause the thread forming blades to cut threads into the lead shaft127 and would cause the plunger 134 to move toward the infusionmedium-retaining interior portion 128 of the reservoir 126.

Alternatively, or in addition, the lead shaft 127 may be coated orwrapped with one or more layers 143 of a seal material, as shown in FIG.21. The seal material layer 143 may include, but is not limited torubber, silicone rubber, polyurethane or other plastic material, orother material having suitable elasticity and flexibility to allow thethreads of the plunger head 134 to operatively engage the coated orwrapped threads of the lead shaft 127. In yet further embodiments, theinner surface of the central channel in the plunger head may be providedwith seals 140 or sealing material 143, in addition to or as analternative to seals or sealing material on the shaft 127.

The shaft 127 has a connection end 150, for connection to a matingconnection end 152 of a drive linkage 154. The drive linkage 154 may bea direct connection to the drive shaft of a motor 144, such that theconnection end 152 of the drive linkage 154 rotates with the rotarydrive motion of the drive shaft of the motor 144. In other embodiments,the drive linkage 154 may include one or more gears, belts, chains,drive shafts or other linkage structure (not shown) for transferringdrive force from a motor 144 to rotational motion of the connection end152 of the drive linkage. The motor 144 may be any suitable drive devicefor rotatably driving the connection end 152 of the drive linkage(either directly or through one or more gears, belts, chains, driveshafts or other linkage structure), including, but not limited to theexample drive devices described above with respect to the motor 44 inFIG. 4 and escapement wheel arrangements in FIGS. 16 a-16 d.

The motor 144 and any gears, belts, chains, drive shafts or otherlinkage structure for coupling the motor 144 to the drive linkage 154may be contained within the interior of the housing structure of thedurable portion 122. The drive linkage or the drive shaft of the motor144 may extend through an aperture in a wall 160 of the housingstructure of the durable portion 122. A seal 162 may be provided withinor adjacent the aperture in the wall 160, to inhibit the passage of oneor more of moisture, air, biological materials or infusion media intothe interior of the housing structure of the durable portion 122. Theseal 162 may include, but is not limited to, one or more o-ring sealsdisposed around the aperture in the wall 160 or around the portion ofthe drive linkage or drive shaft that extends through the aperture inthe wall 160. The seal 162 may be made of any suitable sealing material,including, but not limited to rubber, silicone rubber, polyurethane orother plastic material, metal, composite material or the like.

The connection end 152 of the drive linkage 154 and the connection end150 of the lead shaft 127 are configured to connect to each other whenthe durable portion 122 is coupled to the disposable portion 120 and todisconnect from each other when the durable portion 122 is separatedfrom the disposable portion 120. For example, the connection ends 150and 152 of the lead shaft 127 and the drive linkage 154, respectively,may include mating features that are configured to easily engage witheach other when the connection ends 150 and 152 are brought together anddisengage from each other when the connection ends 150 and 152 are movedapart. In addition, the mating features allow the transfer of rotationalmotion from the drive linkage 154 to the lead shaft 127, when theconnection ends 150 and 152 are engaged.

In one example embodiment as shown in FIG. 22, the mating features mayinclude a slot 164 formed on the connection end 150 of the lead shaft127 and a tab 166 extending from the connection end 152 of the drivelinkage 154, where the tab 166 is shaped to fit within the slot 164 toconnect the lead shaft 127 in rotational communication with the drivelinkage 154. Alternatively, the slot 164 may be formed on the connectionend 152 of the drive linkage 154 and the tab 166 may extend from theconnection end 150 of the lead shaft 127. The shape of the tab 166 andthe slot 164 in FIG. 20 have a generally rectangular cross-sectionaldimension (in the cross-section plane perpendicular to the longitudinaldimension of the lead shaft 127). Other embodiments may employ a tab andslot arrangement with other non-circular cross-sectional shapes (in thecross-section plane perpendicular to the longitudinal dimension of thelead shaft 127) to allow communication of rotational motion from thedrive linkage 154 to the lead shaft 127. In further alternativeembodiments, the mating features may be other shapes that can be readilyengaged together to communicate rotational motion from the drive linkageto the lead shaft 127 and readily separated to allow the durable portion122 to be removed from the disposable portion 120 of the deliverydevice. Such other shapes include, but are not limited to, matingstar-shaped structures, cross-shaped structures, non-circular matingshapes (e.g., oval, partially oval, polygonal or partially polygonal), amating pattern of projections and recesses, or the like, on theconnection ends 150 and 152.

In the delivery device embodiments described above, a plunger head 34 or134 is driven within a reservoir 26 or 126 to drive the infusion mediumfrom the reservoir. Further embodiments of mechanisms for driving aplunger head within a reservoir of a delivery device are described withreference to FIGS. 23-27.

In the embodiment of FIG. 23, a reservoir 226 employs a moveable plungerhead 234. The reservoir 226 and the plunger head 234 may be similar tothe reservoir 126 and plunger head 134 described above with respect toFIG. 18, except that the plunger head 234 need not include a threadedcentral channel. The plunger head 234 includes seals 236 similar to theseals 136 on the plunger head 134 described above with respect to FIG.18. The plunger head 234 and reservoir 226 may include further structureto inhibit rotation of the plunger head within the reservoir 226, forexample, as described above with respect to example structure forinhibiting rotation of the plunger head 134, including, but not limitedto, structure described above with respect to FIG. 19. The reservoir 226may include a septum 230, similar to the septa 30 and 130 describedabove. The septum 230 may be used for refilling the reservoir 226 and/orfor receiving a hollow needle or cannula to provide a fluid flow path toa patient-user, as described above with respect to the septa 30 and 130.

A slide tube 240 is configured to engage the plunger head 234. The slidetube 240 includes a generally hollow, cylindrical tube made of asuitably rigid material, such as, but not limited to, metal, plastic,ceramic, composite material or the like. One end of the cylindricalslide tube 240 is provided with a mating feature 242 for mating with acorresponding mating feature 244 on the plunger head 234. In theembodiment of FIG. 23, the mating feature 242 includes a projection thatextends from the end of the slide tube 240 in the axial direction of thecylindrical shape of the slide tube, while the mating feature 244includes a recess in the exterior-facing side of the plunger head 234.The recess 244 has a shape adapted to receive the projection 242, whenthe end of the slide tube 240 is brought into engagement with theexterior-facing side of the plunger head 234. The recess 244 andprojection 242 may have corresponding, mating shapes having non-circularcross-sectional dimensions (in the cross-section plane perpendicular tothe axis A₅) that inhibit relative rotation between the slide tube 240and the plunger head 234. In another embodiment (as shown in FIG. 24),the plunger head 234 may be connected to (or unitary with) a sleeve 240that has a hollow interior. The sleeve 240 in FIG. 24 may have aslot-like opening along its longitudinal dimension through which arotary drive screw 248 may be received. The slot-like opening in thesleeve 240 may be smaller than the diameter of the rotary drive screw248 and the sleeve 240 may be made of a suitably elastically flexiblematerial to allow the dive screw 248 to be snap fit into the hollowinterior of the sleeve 240, through the slot-like opening in the sleeve240.

The slide tube 240 (in either of the embodiments of FIGS. 23 and 24) hasa generally hollow interior and an interior surface 246 that is threadedalong at least a portion of its length. The rotary drive screw 248includes a shaft that extends coaxially with the slide tube 240. Thedrive screw 248 shaft extends through one end (opposite to the endconnected to the plunger head) of the slide tube 240. One end of thedrive screw 248 shaft extends into the interior of the slide tube 240and an opposite end of the drive screw 248 shaft extends outside of theslide tube 240. The drive screw 248 may be threaded along its length (asshown in FIG. 24) or may have a threaded head 249 coupled to the drivescrew shaft (as shown in FIG. 23). The threads along the length of thedrive screw 248 or the threaded head 249 has threads of a pitch anddiameter for engaging and mating with the threads on the threadedinterior surface 246 of the slide tube 240. In that arrangement,rotation of the drive screw 248 results in a linear movement of theslide tube 240 along the direction of the axis A₅ of the slide tube 240.By rotating the drive screw with a rotary drive device in theappropriate direction, the slide tube pushes the plunger head 234 towardthe septum end of the reservoir 226, to force infusion medium through ahollow needle or cannula, to a patient-user.

The end of the drive screw 248 shaft that is external to the slide tube240 is coupled to a drive device, through suitable drive linkage, torotate the drive screw 248 in a controlled manner. In the embodimentshown in FIG. 23, the drive device includes a linear actuator 250, suchas a piezoelectric actuator device that expands in a linear direction,upon the application of a suitable electrical drive signal. The actuator250 is arranged to frictionally engage and rotate a rotary wheel 252 asmall amount in the direction of arrow 256 with each linear expansion ofthe actuator 250. The actuator 250 may be selectively controlled todrive the rotary wheel 252 in the direction of arrow 256 for dispensinginfusion medium from the reservoir 226, and in the direction opposite tothe direction of arrow 256, to retract the plunger head 234 and allowreplacement of the reservoir 226. A spring 254 or other suitablestructure may be provided to force the actuator 250 against the rotarywheel 252 during expansion of the actuator. The rotational motion of therotary wheel 252 is transferred to rotational motion of the drive screw248, through suitable transfer gearing 258. According to the arrangementshown in FIG. 21, the linear actuator 250 may be selectively energizedto rotate the wheel 252, which rotates the drive screw 248, which causesthe slide tube 240 to move axially and push the plunger head 234 towardthe septum end of the reservoir 226, in a controlled, step-like manner.

While FIG. 23 shows a linear drive device that includes a linearactuator for rotatably driving the drive screw 248, other embodimentsmay employ other drive devices operatively coupled to drive the drivescrew 248. For example, FIG. 24 shows an embodiment in which the drivedevice includes a DC pancake motor 260 that is operatively coupled tothe external end of the drive screw 248, through any suitable interfacegear arrangement 262. In further embodiments, the drive screw 248 may beoperatively coupled to any suitable drive device for rotatably drivingthe drive screw 248 in a controlled manner, including, but not limitedto the example drive devices described above with respect to the motor44 in FIG. 4 and escapement wheel arrangements in FIGS. 16 a-16 d.

As shown in FIG. 23, the slide tube 240 may be supported within aportion of a housing structure 266, such as the housing structure of adurable portion of a delivery device. The slide tube 240 extends throughan opening in the housing structure 266 to engage the plunger head 234.One or more seals 268 may be disposed around the opening in the housingstructure 266 and/or the slide tube 240, to protect the drive devicefrom, for example, moisture, air, biological material or infusion media.The seal(s) 268 may be o-ring seals or other suitable seals made of anysuitable seal material, including, but not limited to, the sealmaterials described above with respect to the seal(s) 45. In addition,an anti-rotation structure may be provided, to inhibit rotation of theslide tube 240 about the axis A₅, relative to the housing structure 266.In one embodiment, the anti-rotation structure may include a projection241 extending from the slide tube 240, for engaging a stop surface 243that is fixed relative to the housing structure 266. In otherembodiments, the seal(s) 268 may provide sufficient frictionalengagement with the slide tube and/or the housing structure 266, toinhibit rotation of the slide tube 240 about the axis A₅, relative tothe housing structure 266.

The reservoir 226 may be located within a disposable housing portion,while the slide tube 240, drive screw 248 and drive device 250 or 260may be located within a durable housing portion that can selectivelycouple to or separate from the disposable housing portion, as describedabove with respect to embodiments of FIGS. 1-22. In a furtherembodiment, as shown in FIG. 25, a delivery device includes a disposablehousing portion 320 having a reservoir retaining portion 324 forcontaining multiple reservoirs 326 (two in FIG. 25). A piston plungerhead 334 is located in each reservoir 326 and may be operated by a slidetube arrangement similar to that shown in either of FIG. 23 or 24 orother suitable piston moving structure. The delivery device in FIG. 25includes a durable housing portion 322 for containing one or more drivedevices 344 and linkage 362 (which may include, for example bevel gearspinion gears or other suitable gear arrangements) for coupling the drivedevice(s) to the reservoirs 326. For example, a drive device, slide tubeand drive screw arrangement as described with respect to FIGS. 23 and 24may be included in the durable housing portion 322.

The embodiment of FIG. 26 employs a reservoir 326, plunger head 334,seals 336 and seals 368, similar to the reservoir 226, plunger head 234,seals 236 and seals 268 described above with respect to FIG. 23. Theembodiment of FIG. 26 also includes a slide tube 340, similar to theslide tub 240 of FIG. 23, except that the slide tube 340 need notinclude a threaded interior surface. Instead, the slide tube 340 in FIG.26 is operatively coupled to a drive device 344 in the form of a linearmotor comprising one or more (two in FIG. 26) piezoelectric stacks 346compressed on a drive shaft 348. The drive shaft 348 may be fixed to adurable portion 366 of delivery device, similar to the durable portion266 described above.

The linear motor drive device 344 may be selectively energized byselectively applying electrical control signals to the piezoelectricstacks to cause the slide tube 340 to move toward the septum end of thereservoir 326, to selectively force infusion medium out of thereservoir, as described above with respect to the reservoir 226 in FIG.23. However, the linear motor drive device 344 of FIG. 26 may beconsiderably smaller and may consume less power than some of the drivedevices and linkages described above for creating rotary motion to drivethe slide tube 240 of FIG. 23.

A further embodiment of a delivery device shown in FIG. 27 includes areservoir 426 and a moveable plunger head 434 within the interior of thereservoir 426. The reservoir 426 and plunger head 434 may be similar tothe reservoir 326 and plunger head 334 of FIG. 26, except that theplunger head 434 need not have a mating feature for engaging a slidetube. Instead, the plunger head 434 is configured to abut an expandablebellows 436 and move along the direction of the longitudinal axis A₆ ofthe reservoir 426 with the expansion of the bellows 436.

The bellows 436 is any suitable expandable structure that includes aninterior volume that is expandable and that is capable of containing ahydraulic fluid. The delivery device in FIG. 27 includes a secondreservoir 438 for containing hydraulic fluid, a conduit or tube 440connected to the hydraulic fluid reservoir 438 and the bellows 436, forproviding a fluid-flow communication path between the hydraulic fluidreservoir 438 and the interior volume of the bellows 436. A pumpingmechanism 444 is provided to selectively pump hydraulic fluid into thebellows 436.

In the embodiment shown in FIG. 27, the pumping mechanism 444 is aperistaltic pump device including a rotor 446 mounted for rotation aboutan axis R. The rotor 446 has a plurality of rollers or pads arranged toengage a portion of the conduit 440 and roll or slide along a length ofthe conduit 440. The conduit 440 may be elastically flexible, at leastalong the length engaged by the rotor 446 rollers or pads. The length ofthe conduit 440 engaged by the rotor 446 may be arranged along anarcuate surface 448, where the arc of the surface 448 corresponds to thediameter of the rotor 446. The arcuate surface 448 may be a surface of awall or other structure formed within the durable housing portion 422.

By rolling across the conduit 440 on the arcuate surface 448, the rotorrollers or pads may engage and squeeze the conduit 440 during the periodof motion of the rollers or pads along the length of the arcuate surface448. The rolling or sliding motion of the rotor rollers or pads alongthe arcuate length of the flexible conduit 440 creates a sufficientpressure differential to drive hydraulic fluid from the hydraulic fluidreservoir 438 to the interior of the bellows 436, in a manner controlledby the controllable rotary motion of the rotor 444. Any suitable rotarydrive device or arrangement, such as, but not limited to those describedherein, may be employed to drive the rotor 444 in a controlled manner.

As hydraulic fluid is pumped into the bellows 436 by the pumpingmechanism 442, the hydraulic fluid creates a fluid pressure within thebellows sufficient to cause the bellows to expand an amount dependentupon the amount of hydraulic fluid pumped into the bellows. As thebellows 436 expands, the end of the bellows that abuts the plunger head434 is moved toward the septum end of the reservoir 426 and pushes theplunger head 434 toward the septum end of the reservoir 426. As theplunger head 434 is moved toward the septum end of the reservoir 426,the plunger head forces infusion medium within the reservoir 426 outthrough a suitable hollow needle or cannula, to a patient-user.

While the embodiment of FIG. 27 employs a peristaltic pump device 444 todrive hydraulic fluid from the hydraulic fluid reservoir 438 to thebellows 436 in a controlled manner, other embodiments may employ othersuitable pump devices for performing that function, including, but notlimited to, conventional piston pumps, impeller pumps, membrane pumps,or the like.

In the embodiment shown in FIG. 27 the reservoir 426 may be located in adisposable portion 420 of the delivery device, while the hydraulic fluidreservoir 438, hydraulic fluid pump device 444, pump drive motor (notshown) and bellows 436 may be located in a durable portion 422 of thedelivery device. The disposable portion 420 and durable portion 422 maybe configured to be coupled together for operation, or separated forservicing, as described above with respect to disposable portion 20 anddurable portion, 22 in FIGS. 2 and 3. The disposable portion 420 may beprovided with a needle insertion mechanism, for inserting a hollowneedle or cannula into a patient-user's skin and connecting the hollowneedle or cannula in fluid flow communication with the interior of thereservoir 426, when the disposable portion 420 is secured to apatient-user's skin, as described above with respect to the disposableportion 20 of FIGS. 2 and 3. Examples of mechanisms that may be used forinserting a hollow needle or cannula into a patient-user and couplingthe needle and cannula in fluid flow communication with a reservoir aredescribed in U.S. patent application Ser. No. 11/211,095, filed Aug. 23,2005, and U.S. Patent Application No. 60/839,840, titled INFUSION MEDIUMDELIVERY SYSTEM, DEVICE AND METHOD WITH NEEDLE INSERTER AND NEEDLEINSERT DEVICE AND METHOD, filed Aug. 23, 2006, (047711-0384). Otherneedle/cannula insertion tools may be used (or modified for use) toinsert a needle and/or cannula, such as for example U.S. patentapplication Ser. No. 10/389,132 filed Mar. 14, 2003, and entitled “AutoInsertion Device For Silhouette Or Similar Products,” and/or U.S. patentapplication Ser. No. 10/314,653 filed Dec. 9, 2002, and entitled“Insertion Device For Insertion Set and Method of Using the Same,” bothof which are incorporated herein by reference in their entirety.

In embodiments described above, the disposable housing portion (e.g., 20in FIG. 3) is provided with a base portion 21 that may be secured to thepatient-user's skin by, for example, but not limited to, an adhesivematerial provided on the bottom surface of the base portion 21. Thatarrangement is generally represented, in side view, in FIG. 26, whereinan adhesive material 101 is provided on the bottom surface (skin-facingsurface) of the base 21 of the disposable housing portion 20. As shownin FIGS. 2, 3 and 28, the durable housing portion 22 may be configuredto be arranged on the base 21 of the disposable housing portion 20 toengage and connect to the disposable housing portion 22. In such anarrangement, the base 21 may be disposed between the durable housingportion 22 and the patient-user's skin, during operation, such that onlythe base 21 of the disposable housing portion remains in contact withthe patient-user's skin, during operation.

However, in other embodiments, the durable housing portion 22 and thedisposable housing portion 20 may be configured to engage each other ina side-by-side arrangement, for example, as represented in FIG. 29. Inthe side-by-side arrangement in FIG. 29, either one or both of thedurable housing portion 22 and the disposable housing portion 20 may beprovided with a base having an adhesive material 101 (and a peelablecover layer 23 as shown in FIG. 3).

In yet further embodiments, as represented by FIG. 30, one or both ofthe durable housing portion 22 and the disposable housing portion 20 maybe attachable and detachable from a separate base member 21′. Suitableconnecting structure, such as described above for connecting the durablehousing portion and the disposable housing portion together, may beemployed for connecting the durable housing portion and the disposablehousing portion to the base member 21′. The separate base member 21′ mayinclude a generally flat, plate-like structure made of any suitablyrigid material including, but not limited to, plastic, metal, ceramic,composite material or the like. The base member 21′ has a surface (theupper-facing surface in FIG. 30) to which the disposable housing portion20 and the durable housing portion 22 may be attached. The base member21′ has a second surface (the lower-facing surface in FIG. 30) to whichan adhesive material and a peelable cover film may be applied, asdescribed above, to allow the base member 21′ to be secured to apatient-user's skin.

The base member 21′ may include a needle inserter device 25, asdescribed above. Examples of suitable needle inserter devices aredescribed in U.S. patent application Ser. No. 11/211,095, filed Aug. 23,2005, and U.S. Patent Application No. 60/839,840, titled INFUSION MEDIUMDELIVERY SYSTEM, DEVICE AND METHOD WITH NEEDLE INSERTER AND NEEDLEINSERT DEVICE AND METHOD, filed Aug. 23, 2006, (attorney docket no.047711-0384), each of which is incorporated herein by reference in itsentirety. In such embodiments, the base member 21′ may be secured to apatient-user's skin. Then, the needle inserter 25 may be activated toinsert a hollow needle or cannula into the patient-user's skin. Then,after the hollow needle or cannula is inserted, the durable housingportion 22 and the disposable housing portion 20 may be attached to thebase member 21′, to connect the reservoir within the disposable housingportion 20 in fluid flow communication with the hollow needle orcannula. In one embodiment, the durable housing portion 22 and thedisposable housing portion 20 may be connected together (for example, inthe manner described above) before attaching those housing portions tothe base member 21′. In a further embodiment, one of the durable anddisposable housing portion is attached to the base member 21′ before thedurable and disposable housing portions are connected together. In suchfurther embodiment, the needle inserter device may be activated toinsert a hollow needle or cannula into the patient-user's skin after thedisposable housing portion is attached to the base member 21′ (eitherbefore or after the durable and disposable housing portions areconnected together).

Alternatively, reference number 25 may represent an opening in the basemember 21′ that aligns with a needle inserter device (or aligns with afurther opening) located in the disposable housing portion 20, when thedisposable housing portion 20 is attached to the base member 21′. Insuch embodiments, the base member 21′ may be secured to thepatient-user's skin. Then the disposable housing portion 20 is attachedto the base member 21′ (either before or after the durable anddisposable housing portions are connected together). Once the disposablehousing portion 20 is attached to the base member 21′, the needleinserter device 25 may be activated to insert a hollow needle or cannulainto a patient-user's skin (either before or after the durable anddisposable housing portions are connected together). Otherneedle/cannula insertion tools may be used (or modified for use) toinsert a needle and/or cannula, such as for example U.S. patentapplication Ser. No. 10/389,132 filed Mar. 14, 2003, and entitled “AutoInsertion Device For Silhouette Or Similar Products,” and/or U.S. patentapplication Ser. No. 10/314,653 filed Dec. 9, 2002, and entitled“Insertion Device For Insertion Set and Method of Using the Same,” bothof which are incorporated herein by reference in their entirety.

Also, while embodiments described above may include an on-board needleor cannula injector device that may be activated through the operator oropening 25, other embodiments may employ an injection site module 103that is external to the disposable housing portion 20, but connected tothe disposable housing portion 20, through a suitable conduit 102, asshown in FIG. 31. The external injection site module 103 may include aneedle or cannula injector device structure and an operator or opening(similar to the operator or opening 25 described above) through whichthe injector device may be activated. Alternatively or in addition, theexternal injection site module 103 may include an infusion set such as,but not limited to an infusion set as described or referenced in U.S.patent application Ser. No. 10/705,686, filed Nov. 10, 2003, titled“Subcutaneous Infusion Set” (Publication No. 2005/0101910) and/or U.S.patent application Ser. No. 11/004,594, filed Dec. 3, 2004, titled“Multi-Position Infusion Set Device And Process” (Publication No.2006/0129090), each of which is assigned to the assignee of the presentinvention and each of which is incorporated herein by reference, in itsentirety.

The conduit 102 that connects the module 103 with the disposable housingportion 20 may be any suitable tubing structure having a fluid flowpassage, such as, but not limited to, a flexible tube made of plastic,silicone or the like. An adhesive material may be provided on the tubingstructure (or between the tubing structure and the patient-user's skin)to secure the tubing to the patient-user's skin. By locating theinjection site module 103 external to the disposable housing portion 20,the disposable housing portion 20 and the durable housing portion 22 maybe clipped to a patient-user's clothing, belt, suspender or otherarticle of apparel or may be held in a pocket of an article of apparelor carried in a purse or the like.

In one embodiment, the conduit 102 may be fixed at one end to thedisposable housing portion 20, in fluid-flow communication with thereservoir within the disposable housing portion 20, and fixed at asecond end to an external injection site module 103, for connection influid-flow communication with a hollow needle or cannula, as describedabove. In further embodiments, one or both of the ends of the conduit102 may include suitable connection structures that allow the conduitends to be selectively connected in fluid-flow communication with, andselectively disconnected from the disposable housing portion 20 and/orthe injection site module 103. Such connectors may comprise a hollowneedle and septum, a Luer connector, or other suitablefluid-communication connectors. In such embodiments, the disposablehousing portion 20 and the durable housing portion 22 may bedisconnected from the module 103, for example, by disconnecting one ofthe ends of the conduit 102 from the module 103 or the disposablehousing portion 20, while leaving the module 103 in place (withoutrequiring the patient-user to withdraw the needle or cannula and, later,insert a needle or cannula to resume operation). In this manner, apatient-user may readily disconnect and remove the disposable housingportion 20 and durable housing portion 22, for example, to allow thepatient-user to shower, bathe, swim or conduct other activities, yetalso allow the patient-user to readily re-connect the disposable housingportion 20 to the module 103, for example, upon completion of suchactivities. Examples of connectors can be found in U.S. patentapplication Ser. No. 10/328,393 filed Dec. 22, 2003, and entitled“Reservoir Connector,” and U.S. Pat. No. 5,545,152 issued Aug. 13, 1996,and entitled “Quick-Connect Coupling For A Medication Infusion System,”both of which are incorporated herein by reference in their entirety. Inother alternatives, different connectors such as Luer locks, or the likemay be used.

In yet further embodiments, the conduit 102 may be eliminated and aninjection site module 103 may be directly connected with the disposablehousing portion 20, as shown in FIG. 32. In such an embodiment, one ormore suitable fluid flow passages are provided through the disposablehousing portion 20 and into the injection site module 103, forfluid-flow communication between the reservoir in the disposable housingportion 20 and a hollow needle or cannula, as described above. Also, insuch embodiments, the injection site module 103 and the disposablehousing portion 20 may include mating connection structures to allow theinjection site module 103 and the disposable housing portion 20 to beselectively connected and disconnected from each other.

Various examples of mating arrangements, for directly connecting aninjection site module 103 to a disposable housing portion are describedwith reference to FIGS. 33-40. FIGS. 33-35 show an example arrangement,in which an injection site module 103 includes at least one (two in FIG.33) protruding engagement pawl 174 that are configured to be received ina corresponding number of receptacles on the disposable housing portion20 (similar to the pawls 74 and receptacles 76 described in U.S. PatentApplication No. 60/839,741, titled INFUSION PUMPS AND METHODS ANDDELIVERY DEVICES AND METHODS WITH SAME, filed Aug. 23, 2006, (attorneydocket no. 047711-0385), which has been incorporated herein byreference. In other embodiments, the pawl(s) 174 may be located on thedisposable housing portion 20, while the corresponding receptacles maybe located on the module 103. In yet other embodiments, each of thedisposable housing portion 20 and the module 103 may include one or morepawls and one or more receptacles.

The pawls 174 and receptacles may be configured to allow a patient-userto manually slide the pawls into the receptacles as the disposablehousing portion 20 and the module 103 are brought together. When thepawls 174 are received in the corresponding receptacles, the module 103is secured to the disposable housing portion 20. The pawls 174 mayinclude a shaped portion or head to provide a snap-fit with thereceptacles, when the pawls 174 are fully received within thereceptacles. The pawls 174 may be configured with sufficient flexibilityto allow the patient-user to separate the disposable housing portion 20from the module 103, by applying a sufficient force to pull those twoparts away from each other and unsnap the pawls 174 from thereceptacles. In the embodiment of FIGS. 33-35, the module 103 may beattached to or may include a base portion 450 that may be secured to apatient-user's skin during operation, in lieu of the extended base 21 ofthe disposable housing portion 20 described above. The base portion 450may include an adhesive material as described herein with respect to thebase 21 of the disposable housing portion 20.

As shown in FIG. 35, the embodiment of FIGS. 33-35 may be formed inthree general parts, including the disposable housing portion 20, thedurable housing portion 22 and the module 103 on the base portion 450.The durable housing portion 22 and the disposable housing portion 20 maybe secured together (as shown in FIG. 33), and the combined, connecteddisposable and durable housing portions may be secured to the module 103and base portion 450. In one embodiment, the base portion 450 may besecured to a patient-user's skin, before the combined, connecteddisposable and durable housing portions are secured to the module 103and base portion 450. In a further embodiment, the combined, connecteddisposable and durable housing portions are secured to the module 103and base portion 450, before the base portion 450 is secured to thepatient-user's skin.

Another example of a connection structure is described with reference toFIGS. 36 and 37, wherein the module 103 includes a shaped head 452configured to be received within a correspondingly shaped opening orreceptacle in the disposable housing portion 20. The shaped head 452 maybe configured with a shape that allows the head to be received in thereceptacle when the disposable housing portion 20 is aligned relative tothe module 103 in a first alignment position, as shown in FIG. 36, andfurther allows the disposable housing portion 20 to be rotated relativeto the module 103 while the head 452 is received within the receptacleto a second alignment position as shown in FIG. 37. The receptacle inthe disposable housing portion 20 may be shaped to allow the head 452 tobe freely received or removed from the receptacle, when the disposablehousing portion 20 is in the first alignment position (FIG. 36), yetabut the head 452 and inhibit separation of the head 452 from thereceptacle (and, thus, inhibit separation of the disposable housingportion 20 from the module 103), when the disposable housing portion isin the second alignment position (FIG. 37).

A further example of a connection structure is described with referenceto FIGS. 38-40, wherein the device incorporates three parts, the durablehousing portion 22, the disposable housing portion 20 and a base 456. Ashaped receptacle 454 on the base portion 456 is configured to receive acorrespondingly shaped connector member in the disposable housingportion 20. In FIGS. 38-40, the module 103 is formed, integral with thedisposable housing portion 20. The shaped receptacle 454 may beconfigured with a shape that allows the connector member in module 103to be engaged with the receptacle 454, when the disposable housingportion 20 is aligned relative to the base 456 and receptacle 454 in afirst alignment position, as shown in FIG. 38, and further allows thedisposable housing portion 20 to be rotated relative to the base 456 andreceptacle 454, while the receptacle 454 is engaged within the connectormember, to a second alignment position as shown in FIG. 39. Thereceptacle 454 and the connector member in the disposable housingportion 20 may be shaped to allow the connector member to be freelyengage the receptacle 454, when the disposable housing portion 20 is inthe first alignment position (FIG. 38), yet lock with the receptacle 454and inhibit separation of the connector member from the receptacle (and,thus, inhibit separation of the disposable housing portion 20 from themodule 103), when the disposable housing portion is in the secondalignment position (FIG. 39). The receptacle 454 and connection membermay include any suitable known rotary connection structures forconnecting two structures together upon engagement and relative rotationof the two structures in one direction, yet allow the two structures tobe disengaged and separated from an engaged arrangement, by relativerotation of the two structures in the second, opposite direction. Amotion inhibiting structure, such as a locking tab, pawl or the like,may be provided to inhibit relative motion between the disposablehousing portion 20 and the base 456, once those parts have beenconnected, as described above.

As shown in FIG. 40, the embodiment of FIGS. 38-40 may be formed inthree general parts, including the disposable housing portion 20, thedurable housing portion 22 and the module 103 on the base portion 456.The durable housing portion 22 and the disposable housing portion 20 maybe secured together (as shown in FIG. 38), and the combined, connecteddisposable and durable housing portions may be secured to the baseportion 456. In one embodiment, the base portion 456 may be secured to apatient-user's skin, before the combined, connected disposable anddurable housing portions are secured to the base portion 456. In afurther embodiment, the combined, connected disposable and durablehousing portions are secured to the base portion 456, before the baseportion 456 is secured to the patient-user's skin.

In yet further embodiments, the injection site module may be formed as aunitary structure with the disposable housing portion 20. Also, in anyof the embodiments described above, one or more sensors may be locatedin the disposable housing portion 20, the injection site module 103 orthe durable housing portion 22, for sensing a biological condition,including, but not limited to, blood glucose level, level of infusionmedium in the patient-user's blood and/or other conditions. Suchsensor(s) may include a hollow needle or cannula and/or a set ofmicro-needles, as described above, for piercing the patient-user's skinto convey fluid from the patient to the sensor.

Various aspects of the multiple embodiments described above may beemployed independently or in combinations thereof. Significantadvantages can be obtained from various embodiments and combinationsdescribed herein, wherein an at-site delivery system may be made of twoparts, including a disposable portion and a non-disposable portion. Thedisposable portion may contain all materials that are in direct contactwith the infusion medium, such as reservoir body, reservoir piston,septum systems and injection needle. The non-disposable portion couldcontain substantially the materials that are not in contact with themedication including the drive system, pressure or force sensing system,battery, electronics, display, and non-disposable housing. The pumpcould be designed such that the disposable portion (with an unused new,user-filled, prefilled, refurbished, remanufactured or re-filledreservoir 26) is inserted into the non-disposable portion. Bysimplifying the manner in which the disposable portion of the deliverydevice can be replaced and by simplifying the manner in which thedelivery device can be re-activated after replacing a disposableportion, a greater number of patient-users will be able to use andbenefit from such delivery devices.

While particular embodiments of the present invention have been shownand described, it will be obvious to those skilled in the art that theinvention is not limited to the particular embodiments shown anddescribed and that changes and modifications may be made withoutdeparting from the spirit and scope of the claimed invention. Forexample, while embodiments described above may include an adhesivematerial and a cover film 23 (FIGS. 2 and 3), further embodiments mayinclude a plurality of adhesive material layers alternating with acorresponding plurality of cover film layers 23, to allow the deliverydevice to be secured, removed and re-secured to the patient-user's skinone or more times.

In such embodiments, a first cover film layer located at the end of thestack of alternating layers of adhesive material and cover film, may beremoved to expose a first layer of adhesive material. With the firstlayer of adhesive material exposed, the delivery device (or componentthereof) may be adhered to a patient-user's skin, as described above.After a suitable period of usage, the delivery device (or componenthaving the adhesive) may be removed from the patient-user's skin, forexample, for servicing, re-filling, replacement of one or morecomponents, or the like. After removal of the delivery device (orcomponent) from the patient-user's skin, a second cover film layer onthe delivery device (or component) may be removed to expose a secondlayer of adhesive material. With the second layer of adhesive materialexposed, the delivery device (or component) may be secured to the samepatient-user or, in certain contexts, to a different patient-user, forfurther operation. The process may be repeated a number of times up tothe number of adhesive material and cover film layer pairs are includedin the plural alternating layers of adhesive material and cover film.

In addition, while embodiments described above include an injection sitelocated on the disposable housing portion 20 or in an external injectionsite module 103, other embodiments may employ an injection site locatedin the durable housing portion 22 and connected, through suitablefluid-flow passages, to the reservoir in the disposable housing portion20, when the durable housing portion and disposable housing portion areengaged. Also, while embodiments are described above in the context ofdelivery devices for delivering an infusion medium from a reservoir to apatient-user, other embodiments may be operated to withdraw a fluidicmedium from a patient-user (or other source) and transfer the fluidicmedium to the reservoir. Such other embodiments may be operated byoperating the drive device to selectively move the piston plunger awayfrom the septum-end of the reservoir (to increase the fluid-retainingvolume of the reservoir) to create a negative pressure sufficient todraw fluid from the patient-user (or other source) to which the hollowneedle or cannula is secured.

Also, various embodiments described above may employ a reservoir 26,126, 226, 326, 426 that, in some examples, may comprise a canister thatis removable from and insertable into the first or disposable housingportion 20. In this manner, a reservoir cartridge may be removed andreplaced with a new, refilled, pre-filled, user-filled, refurbished orremanufactured cartridge. In such embodiments, the reservoir cartridgemay include an electronic storage device (such as an electronic memorychip or the like) for storing information, such as, but not limited to,identification of the contents of the reservoir, identification of themaker of the reservoir or its contents, information relating to thestate of fill or depletion of the reservoir, or the like. Suitableelectrical contact pads located in the disposable housing portion mayelectrically connect with contact pads on the reservoir, to electricallyconnect the electronic storage device on the reservoir canister withsuitable electronics in the disposable housing portion or the durablehousing portion 22, for reading information stored on the electronicstorage device. Such information (or other information, warnings, etc.,associated with the stored information) may be displayed on a displaydevice on the durable housing portion 22, when the reservoir canister isinserted into the disposable housing portion 20, and the disposablehousing portion 20 and the durable housing portion 22 are engaged.

In addition, in any of the above-described embodiments, one or both ofthe disposable housing portion 20 and the durable housing portion 22(and/or a separate base portion 21′ or 450 or a separate injection sitemodule 103) may include a force sensor (not shown) or other suitablesensing device for sensing the proper placement or engagement of one ormore of the disposable housing portion 20 and the durable housingportion 22 (and/or a separate base portion or a separate injection sitemodule) on a patient-user's skin (or other proper location for operationwith the patient). In such an embodiment, further electronics maycontrol the operation of the drive device to inhibit operation of thedrive device and/or the needle injector, unless the sensor senses theproper operable engagement of one or more of the disposable housingportion 20 and the durable housing portion 22 (and/or a separate baseportion or a separate injection site module) with the patient-user'sskin (or other proper location for operation).

Alternatively or in addition, one or both of the disposable housingportion 20 and the durable housing portion 22 may include a sensingdevice (not shown) for sensing the proper operable engagement of thedisposable housing portion 20 and the durable housing portion 22together (and/or with a separate base portion or a separate injectionsite module). In such an embodiment, further electronics may control theoperation of the drive device to inhibit operation of the drive deviceand/or the needle injector, unless the sensor senses the proper operableengagement of the disposable housing portion 20 and the durable housingportion 22 together (and/or with a separate base portion or a separateinjection site module).

In any of the above embodiments, a sensor may be provided in (orotherwise associated with) the reservoir to detect a low volume ofinfusion medium in the reservoir. For example, a sensor may beconfigured to detect a condition at which the volume of infusion mediumin the reservoir reaches a threshold minimal level. A warning device maybe operably connected to the sensor, to provide a warning signal, uponthe detection of a low volume condition. The warning device may providean audible warning sound, a visible warning signal and/or a tactilewarning signal (such as, but not limited to a perceptible vibration) tothe patient-user, upon the detection of the volume of infusion medium inthe reservoir reaching a threshold minimal level. In one embodiment, thevisible warning may be provided as a message on an electronic display(as described above) on the durable housing portion 22. Alternatively orin addition, a warning signal condition may be communicated to anddisplayed on a remote CCD 16 or computer 18 (FIG. 2), for example,through wireless communication electronics as described above.

In addition, while various embodiments described above may include oneor more adhesive layers, each having a peelable cover layer, otherembodiments may employ a single adhesive layer having (or pluraladhesive layers, each having) a pattern of plural peelable cover layerportions, such that a patient-user may peel off one portion of the coverlayer for adhering the delivery device to the patient-user as describedabove, while leaving the rest of the pattern of peelable cover layerportions on the adhesive. In such an embodiment, after completion of afirst period of operation of the delivery device and removal of thedelivery device from the patient-user, a second portion of the peelablecover layer may be removed from the adhesive layer and the deliverydevice may be adhered to a patient-user for a second period ofoperation.

Also, while various delivery device embodiments described above includebase portions (for example, 21, 21′ and 450) that are configured to besecured to a patient-user's skin (or other suitable surface ofoperation) and that extend along the full length and width of thedelivery device structure, other embodiments may employ base portions(that secure to the patient-user's skin or other surface) that areconfigured to be less than the full length or width dimension of thedelivery device structure, to minimize the surface area in contact withthe patient-user (or other surface) and, thus, improve patient-usercomfort during operation. Base portions having shapes and sizesdifferent from those shown in the accompanying drawings may be employedfor additional improvements with regard to patient-user comfort andminimizing surface area in contact with the patient-user. Furthermore,as noted above, the base portion may be composed of a flexible materialthat at least partially conforms to the curvature and movement of thepatient-user's body.

In any of the above-described embodiments in which an adhesive materialis used to secure one or more of the delivery device components to thepatient-user's skin (or other suitable surface for operation), multipletypes of adhesive materials (or multiple strengths of adhesives) may beemployed, such that a stronger adhesive is provided in certain areas(such as around the needle injection site), while a weaker adhesive isprovided in other areas.

1. A delivery device for delivering an infusion medium to a user, the device comprising: a disposable housing portion adapted to be secured to a user; a durable housing portion configured to be selectively engaged with and disengaged from the disposable housing portion to allow disposal of the disposable housing portion without disposing of the durable housing portion; a first reservoir supported by the disposable housing portion, the reservoir having an interior for containing a first fluidic medium and a plunger moveable within the interior of the reservoir along an axial direction of the reservoir; an expandable structure having an interior volume and an end for engaging the plunger and moving the plunger as the expandable structure is expanded, when the disposable housing portion and the durable housing portion are engaged; a second reservoir supported by the durable housing portion, for containing a second fluid medium for expanding the expandable structure; a conduit for coupling the second reservoir to an interior volume of the expandable structure; and a drive device supported by the durable housing portion, for selectively conveying the second fluidic medium through the conduit, from the second reservoir to the interior volume of the expandable structure, to selectively expand the expandable structure, when the first housing portion and the second housing portion are engaged.
 2. A delivery device according to claim 1, wherein the drive device comprises a peristaltic drive device.
 3. A delivery device according to claim 2, wherein the peristaltic drive device comprises a rotatable rotor having a plurality of contact rollers or pads arranged to contact a first length of the conduit as the rotor is rotated, and wherein a support surface is provided on the durable housing portion for supporting at least the first length of the conduit.
 4. A delivery device according to claim 3, wherein the support surface comprises a curved surface.
 5. A delivery device according to claim 1, wherein the drive device comprises a fluid pump.
 6. A delivery device according to claim 3, wherein the drive device further comprises a motor operatively coupled to rotate the rotatable rotor.
 7. A delivery device according to claim 6, further comprising linkage structure coupled to the motor and to the rotatable rotor, to transfer drive force from the motor to the rotatable rotor.
 8. A delivery device according to claim 1, wherein the drive device comprises a rotatable rotor having a plurality of contact rollers or pads arranged to contact a first length of the conduit as the rotor is rotated; and a motor operatively coupled to rotate the rotatable rotor; wherein a support surface is provided on the durable housing portion for supporting at least the first length of the conduit.
 9. A delivery device according to claim 1, wherein the drive device comprises a rotatable rotor having a plurality of contact rollers or pads arranged to contact a first length of the conduit as the rotor is rotated along a radius of curvature, and wherein a curved surface is provided on the durable housing portion for supporting at least the first length of the conduit, the curved surface having a radius of curvature approximating the radius of curvature of the rotor rollers or pads.
 10. A delivery device according to claim 9, wherein the drive device further comprises a motor operatively coupled to rotate the rotatable rotor.
 11. A delivery device according to claim 1, wherein the expandable structure comprises a bellows structure.
 12. A delivery device according to claim 1, wherein the drive device comprises a fluid pump.
 13. A method for making a delivery device for delivering an infusion medium to a user, the method comprising: providing a first housing portion adapted to be secured to a user; providing a second housing portion configured to be selectively engaged with and disengaged from the first housing portion to allow disposal of the first housing portion without disposing of the second housing portion; supporting a first reservoir on the first housing portion, the reservoir having an interior for containing a first fluidic medium; arranging a plunger within the interior of the reservoir and movable along an axial direction of the reservoir; arranging an end of an expandable structure for engaging the plunger and moving the plunger as the expandable structure is expanded, when the first housing portion and the second housing portion are engaged; supporting a second reservoir on the second housing portion, for containing a second fluid medium for expanding the expandable structure; coupling a conduit in fluid flow communication with the second reservoir and an interior volume of the expandable structure; and operatively coupling a drive device for selectively conveying the second fluidic medium through the conduit, from the second reservoir to the interior volume of the expandable structure, to selectively expand the expandable structure, when the first housing portion and the second housing portion are engaged.
 14. A method according to claim 13, wherein operatively coupling a drive device comprises operatively coupling a peristaltic drive device to the conduit.
 15. A method according to claim 13, wherein operatively coupling a drive device comprises supporting a rotatable rotor for rotation and arranging the rotatable rotor having a plurality of contact rollers or pads to contact a first length of the conduit as the rotor is rotated when the first and second housing portions are engaged.
 16. A method according to claim 15, further comprising providing a support surface for supporting the first length of conduit.
 17. A method according to claim 16, wherein the support surface is curved.
 18. A method according to claim 15, wherein operatively coupling a drive device further comprises operatively coupling a motor to rotate the rotatable rotor.
 19. A method according to claim 18, wherein operatively coupling a motor comprises coupling a linkage structure to the motor and to the rotatable rotor, to transfer drive force from the motor to the rotatable rotor.
 20. A method according to claim 19, wherein the support surface is curved.
 21. A method according to claim 13, wherein operatively coupling a drive device comprises supporting a rotatable rotor for rotation, the rotor having a plurality of contact rollers or pads arranged to contact a first length of the conduit as the rotor is rotated along a radius of curvature; and supporting at least the first length of the conduit on a surface in the first housing portion.
 22. A method according to claim 21, wherein supporting at least the first length of the conduit comprises arranging a curved surface to support the first length of the conduit, the curved surface having a radius of curvature approximating the radius of curvature of the rotor rollers or pads.
 23. A method according to claim 22, wherein the expandable structure comprises a bellows structure.
 24. A method according to claim 13, wherein the expandable structure comprises a bellows structure. 